Class A,B, or C Amps
Tinker
quick rundown ?
Thanks,
Tinker
Hillbilly Dave
Dave
KG5XR
Ex. WN5DQG,WB5LWZ,WR5ALP
AAT6YC ARMY MARS
Dave's Radio Electronics
Since 1972
The (little) voice of the Ozarks
http://www.geocities.com/TheTropics/Island/4371/index.html
Tinker <Speed...@hotmail.com> wrote in message
news:7s69s8$m0d$1...@ins22.netins.net...
Bill Eitner
borrowing a copy of The ARRL Handbook or a copy or The Radio Handbook
from a local library and reading the sections that pertain to that.
After you've done that, if you have any specific questions they can
be fielded here.
--
Tinker wrote:
>
> I was wondering what the classes of amps really mean ? Could anyone give me
> quick rundown ?
> Thanks,
> Tinker
--
-------------------------------------------------------------------
-=[Bill Eitner]=-
Link to A.M. Tutorial, rec.radio.cb FAQ
and The Dark Side:
http://kd6tas.conk.com
-------------------------------------------------------------------
Tinker
them will work but some may sound better than others.
Sorry for too such of a broad question.
Tinker
Bill Eitner wrote in message <37E6C71E...@netzero.net>...
Toll Free
Class AB
The Class AB amps (Like Texas Star (on better than stock volts.. About
14.5) Messenger, Palomar, Galaxy, etc) run very well for both AM and SSB.
When you run them on AM, you better run them with a low dead-key, and I
suggest a good fan kit on them, because the amps are inefficient. Translate
this as HIGH HEAT! However, this is the cleanest amplifier class you will
find commonly available. Their is no differentiation as to Class AB1 or
Class AB2, as the differentiation was one of whether grid (base) current was
drawn on a tube... For it to be anything other than Class Ab or B, base
(grid) current must be drawn.... Otherwise, the transistor is not on.
Class B
The Class B amps (X-Force, some Pirate, the old Commander (IF You set the
bias up the correct way..... They had a variable, and worked best at Class
B), and other amps of the same vintage... Basically, battle boxes with
bias, carefully constructed with variable bias, or amps specifically made
this way ... Translate as the diode resistor carefully chosen for a
specific voltage / Base voltage regulated through the use of a Zener, rather
than a normal 1NXXXX diode)... These amps are the more efficient design of
the "Biased" amps. They do not require a lot of drive, being that the gain
is higher... But, with the higher gain, the total saturated power is lower.
You can volt these a little higher (But I don't recommend more than 15.5
volts.... 16 volts for a VERY short period of time), and you get a little
more out... They also put a slightly less draw on the electric system of
your car... Best for all around work.. However, you can usually tell that
the amp is a Class B amp, because the transistor(s) are just barely turned
on, and thier is no (or very little) flywheel effect. However, they are
totally useable for all around use.
Class C
These amplifiers are built for watts.... Nothing more. They sound like
garbage on SSB unless you piledrive the hell out of them, and then all you
are doing is biasing them into Class B... What's the point their.. You
lose the efficiency that you get with a Class C amp. They produce
distortion, harmonics, etc.... But, they produce mo watts. You typically
need more watts to drive them with, because the gain is the lowest of the
common classes of amplifier. You can volt these.... The maximum voltage
depending on the internal design of the amplifier (Interpret this as how
much capacitance is across the transformers.... Typically you see about
1100pF on the output, to limit current drawn by the collectors...) The
Class C amp is also useable on AM, but again, it causes distortion, bleed
and hurts the neighbors. This is a good amp to run in the mobile, as it
lets you run the biggest numbers at the lower current draw... However ,this
is not always true, as people find out, because you must run a bigger
driver.... So, you are right back up their in current draw...
This is a very simplistic approach at teaching the different classes of
operation, and I am sure that people will argue about it. I am basing it on
the ARRL manual for amateur ops, the Radio Handbook, Bill Orr, and my own
measurements with an IFR, Spec An, and an O-Scope.
Your mileage may vary, but you can't argue with the laws of physics.
Hope it helps!
Toll Free
Tinker <Speed...@hotmail.com> wrote in message
news:7s69s8$m0d$1...@ins22.netins.net...
Tinker
exactly what I wanted to hear.
Thanks,
Tinker
Toll Free wrote in message ...
tn...@mucks.net
wrote:
>I was just wondering what class works best with A.M. and SSB . Or if all of
>them will work but some may sound better than others.
>Sorry for too such of a broad question.
>Tinker
I believe this has all ready been answered, but from just the
standpoint of being clean, clean meaning lack of bleed over,
and lack of audible distortion, the amps that do the best are the
ones that are turned on for a greater portion of the RF cycle.
There are a full 360 degrees is one cycle, so that:
A= 360
AB= less than 360 but greater than180
B= 180
C= less than 180
As it has already been mentioned, class AB is the cleanest
amp that will be readily available for RF power amplification.
Class A is just too inefficient to use for RF power purposes.
Toll Free
MR.2SC2879 <mwo...@aol.com2879> wrote in message
news:19990920215039...@ng-fb1.aol.com...
> class ab uses a push pull configuration
You can run any class of operation in the push pull configuration. The
class of operation is independent of the design for push pull or single
ended.
>(which is really efficient)
It is not anymore efficient than a pair of single ended amps coupled.
Efficiency has nothing to do with this.
>of the class b nature
Class B is where you just barely turn the transistors on... .65 to .7 volts
on the base. Any transistor can be run this way... Single ended, or push
pull. Or, even, parallel!
>to push the load
This is a new term that you just made up? Guess so... I have never heard
of "pushing the load", unless you are talking about a cart filled with
something and you are in the back of the cart, applying pressure to make the
car move...
That would be pushing the load..
Or when you have to go to the bathroom real bad, but need metamucile. That
would also be pushing the load.
>and create the sine wave
No, that has nothing to do with it. Wrong again.
but also can create
> some switching distortion
It has nothing to do with switching distortion. You are thinking of what is
commonly referred to as Crossover distortion... That 1.2 to 1.4 volt area
where the transistors are completely turned off when you run with no bias.
Apply .7 volts of bias to the input transformer center tap on a push-pull
configuration, and this problem goes away.
Run it grounded base, and you have this problem.... But, you can have this
same problem when you run a single transistor....
so it also utilizes the class a configuration for the
> input
The input network has nothing to do with the class of operation, other than
the bias is applied to the center tap of a push pull arrangement. It can
also be applied via a choke to a single ended amp stage.
which is extremly clean but very inefficient.
Hey....! You finally got something right! Class A is extremely
inefficient, but it is also high gain!
>
> class c uses the carrier to drive the transistors which is very efficient
but
> very dirty.
No, Class C uses the RF waveform to turn on the transistors.. It might just
be a question of wording, but your words are totally wrong.
I think that you are the same person that came out here a couple days ago
and told us all about your ass kicking amplifiers.
Since it is fairly clear that you have no idea how an amplifier works, I
believe that I will steer clear of you, your amps, and your knowledge...
You have a lot to learn.
> <<<<<<<<MR.2879>>>>>>>>
If we where to equate knowledge with transistors, you would be running at
the MRF 421 level..... Not the 2879. ;-)
Toll Free
MR.2SC2879
class b nature to push the load and create the sine wave but also can create
some switching distortion so it also utilizes the class a configuration for the
input which is extremly clean but very inefficient.
class c uses the carrier to drive the transistors which is very efficient but
very dirty.
<<<<<<<<MR.2879>>>>>>>>
superiorw...@prodigy.net
Toll Free wrote: >>>you can volt these a little higher (But I don't
recommend more than 15.5
>volts.... 16 volts for a VERY short period of time), and you get a little
more out...
You mentioned class AB, how about class C, what can you volt these too
comfortably?
KRS
Hillbilly Dave
think they are.....
Dave
KG5XR & WB5CYX (Club)
EX- WB5LWZ , WN5DQG, WR5ALP
ARMY MARS, AAT6YC
KRH-4063/KRI-0332/KJO-8973
(little voice of the Ozarks)
Daves Radio Electronics
Since 1972
http://www.geocities.com/TheTropics/Island/4371/index.html
<superiorw...@prodigy.net> wrote in message
news:7s7gga$559u$1...@newssvr03-int.news.prodigy.com...
Chris
http://community.webtv.net/thumper485/THUMPER485SQTH
Dillo
The Smokin' Armadillo
Southeastern, PA
wildcat
Are your typing fingers tired because you gave them a workout on this one!
RfWatts1
was really mr.2879 he would know push pull can be done in any configuration
as you said.
Toll Free <toll...@bigradios.com> wrote in message
news:XWBF3.6754$C3.41969@insync...
>
> MR.2SC2879 <mwo...@aol.com2879> wrote in message
> news:19990920215039...@ng-fb1.aol.com...
> > class ab uses a push pull configuration
>
> You can run any class of operation in the push pull configuration. The
> class of operation is independent of the design for push pull or single
> ended.
>
> >(which is really efficient)
>
> It is not anymore efficient than a pair of single ended amps coupled.
> Efficiency has nothing to do with this.
>
> >of the class b nature
>
> Class B is where you just barely turn the transistors on... .65 to .7
volts
> on the base. Any transistor can be run this way... Single ended, or push
> pull. Or, even, parallel!
>
> >to push the load
>
> This is a new term that you just made up? Guess so... I have never heard
> of "pushing the load", unless you are talking about a cart filled with
> something and you are in the back of the cart, applying pressure to make
the
> car move...
>
> That would be pushing the load..
>
> Or when you have to go to the bathroom real bad, but need metamucile.
That
> would also be pushing the load.
>
> >and create the sine wave
>
> No, that has nothing to do with it. Wrong again.
>
> but also can create
> > some switching distortion
>
> It has nothing to do with switching distortion. You are thinking of what
is
> commonly referred to as Crossover distortion... That 1.2 to 1.4 volt area
> where the transistors are completely turned off when you run with no bias.
>
> Apply .7 volts of bias to the input transformer center tap on a push-pull
> configuration, and this problem goes away.
>
> Run it grounded base, and you have this problem.... But, you can have
this
> same problem when you run a single transistor....
>
> so it also utilizes the class a configuration for the
> > input
>
> The input network has nothing to do with the class of operation, other
than
> the bias is applied to the center tap of a push pull arrangement. It can
> also be applied via a choke to a single ended amp stage.
>
> which is extremly clean but very inefficient.
>
> Hey....! You finally got something right! Class A is extremely
> inefficient, but it is also high gain!
>
> >
> > class c uses the carrier to drive the transistors which is very
efficient
> but
> > very dirty.
>
RfWatts1
Chris <thump...@webtv.net> wrote in message :
Toll Free
The amount of capacitance and turns on the output transformer (and to a
little bit, the material the transformer torroids are made of... Mix)
delegate the max volts.
Toll Free
Toll Free
They are still tired... Today!
hehe
Toll Free
wildcat <wil...@tp.net> wrote in message
news:Z0SF3.3409$I6.1...@typ12.nn.bcandid.com...
Bill Eitner
>
> I was just wondering what class works best with A.M. and SSB . Or if all of
> them will work but some may sound better than others.
> Sorry for too such of a broad question.
> Tinker
I'll reply in terms that apply to CBers in general.
As far as power output with solid-state amps, Class
C (unbiased) works best. With SSB, Class B works
best. Some may say that Class AB is better, but
that's only because they haven't seen the latest,
leading-edge research. On the other hand, Class C
(technically unbiased) will produce a readable signal
even on SSB because unbiased solid-state CB amps do
not run with any applied negative bias which would make
them true Class C amps. See how complicated this can
get?
In a nutshell, for SSB use, you're better off with
an amp that's biased into linearity. That means
at least Class B.
This doesn't even skim the top of the huge iceberg
that makes up the debate that's been going on as
long as I've been out here (3 years) about amplifier
class. That's why the big guns out here (including
myself) don't even want to get started on this again.
Here's the scoop as far as CBers are concerned: The
best amplifiers (Dave Made, etc.) run in Class C (un-
biased) with a driver stage to produce more modulation.
On SSB, the same amp switches to Class B or AB and bypasses
the driver stage to increase linearity (accuracy of
amplification) and minimize distortion. This assumes
amps of no more than 8 transistors in the output stage.
See how this works? No bias (technically Class C) and
a ton of drive and DC supply voltage are the keys to
doing well on AM. On SSB it's an entirely different
story. The drive has to be reduced and the bias has
to be present for an amp to sound as best it can on SSB.
This may be confusing, but it's the best I'm willing to
offer and back up (undoubtedly I'll be challenged).
You "Tinker" but you don't know the price you ask others
to pay in order to play your game. This is a complex
newsgroup where arguments and debates flare up over the
most minor points. What looks like a simple question
can blow up into a huge argument/debate.
--
> Bill Eitner wrote in message <37E6C71E...@netzero.net>...
> >That's too big a subject to properly handle in this forum. I suggest
> >borrowing a copy of The ARRL Handbook or a copy or The Radio Handbook
> >from a local library and reading the sections that pertain to that.
> >After you've done that, if you have any specific questions they can
> >be fielded here.
> >--
> >Tinker wrote:
> >>
> >> I was wondering what the classes of amps really mean ? Could anyone give
> me
> >> quick rundown ?
> >> Thanks,
> >> Tinker
> >
> >
Toll Free
j/k
Toll Free
Bill Eitner <kd6...@netzero.net> wrote in message
news:37E8339C...@netzero.net...
Andrew Taylor
500 is one of the best for someone like me who does not want to have to go out
and spend a lot of money on extra voltage, wiring and all that other good stuff.
What would you pair this amp with. I've used Cobra's and Galaxy's but am open
for suggestions. I got out of CB'ing here in my local area because of all the
wild ones that tear up the channels but I sure have missed it and am considering
jumping back in.
Last setup I had was the Galaxy 73V, Palamar 650, Wilson 1000 mag mount. Was
happy with it but I did have problems mentioned in previous post about amp not
wanting to unkey. {real pain in the ass to reach back and turn it off and back
on just to talk).
Thanks.
Toll Free
If you like the legal line of CB radios, then the Uniden 8719 chassis (148,
Grant, etc.) are the best.
I typically see more Bird watts from a Cobra 148 than I do a Galaxy, but the
Galaxy will do more on SSB clearly.
Toll Free
Andrew Taylor <dre...@bellsouth.net> wrote in message
news:37E8391F...@bellsouth.net...
Andrew Taylor
helped here in my area because of all the clutter. I could find a channel to
talk on without excessive bleed from other people nearby. And there were enough
with SSB that even there they sometimes managed to screw it up.
Bottom line, one time purchase, best setup available without having to rewire
automobile, and ability for SSB and possible others.
Off the subject or to change the subject. Can the Galaxy be used as 10 meter
after conversion. If one should ever have a desire to get licensed.
Bill Eitner
>
> Guess this means you didn't like my explanation? ;-)
>
> j/k
I get the joke, but in all honesty I don't know that
I've read your explanation yet. If I did, it didn't
sink in if you know what I mean.
--
> Toll Free
>
> Bill Eitner <kd6...@netzero.net> wrote in message
> news:37E8339C...@netzero.net...
Toll Free
If for some reason you desire 12 meters, 11 meters and 10 meters, and a
better RX section, get one of the Connex 4800DX radios, or the Cobra 148
Export radios (The 12 banders).
They have a new board in them that is supposed to kick ass.
Toll Free
Andrew Taylor <dre...@bellsouth.net> wrote in message
news:37E83D81...@bellsouth.net...
Bill Eitner
>
> O.K. I've read all that you and Toll Free have had to say about this. Texas Star
> 500 is one of the best for someone like me who does not want to have to go out
> and spend a lot of money on extra voltage, wiring and all that other good stuff.
>
> What would you pair this amp with.
You haven't read all the recent posts on this subject. The
dual final radios (10 meter/exports) are a great match to
the Texas Star 500. In my neck of the woods, it's like
bread and butter; you buy a big Galaxy or a 2950 and the
natural match for it is a Texas Star 500. The same goes
for the guys who know what the hot AM-only radios are
(Uniden 66, 76, Cobra 25, 29).
> I've used Cobra's and Galaxy's but am open
> for suggestions. I got out of CB'ing here in my local area because of all the
> wild ones that tear up the channels but I sure have missed it and am considering
> jumping back in.
Nothing has changed. If anything it's gotten worse.
Don't get back in if you think the trouble makers are
gone--they aren't.
> Last setup I had was the Galaxy 73V, Palamar 650, Wilson 1000 mag mount. Was
> happy with it but I did have problems mentioned in previous post about amp not
> wanting to unkey. {real pain in the ass to reach back and turn it off and back
> on just to talk).
The amp was unstable. This time, buy a stable amp like the
Texas Star 500, a Messenger M4V, or a good custom like a
Dave Made or X-Force M200. Also, make sure you have enough
charging system to cover it. For the amps mentioned we're
talking a 100+ amp alternator at least. A real antenna
ground (not a mag-mount) helps tremendously too. The rule
is that serious, hi-power CBers NEVER use mag-mounts.
To make sure the amp is stable, put an SWR meter right at
the output of the amp. Make the SWR as low as it can be
with the amp off, then turn the amp on and recheck. The
SWR will almost always rise, but it shouldn't be in the
red (above 3:1). If it is, the amp is unstable and you'll
have to figure out why and correct the problem before you
use the amp. I can help you with that, but I'd rather do
that via e-mail as it can get complicated. One of the
obvious reasons is that your antenna (aka RF) ground is
inadequate because you're using a mag-mount (remember
your old system and don't do that again).
--
little...@my-deja.com
"Tinker" <Speed...@hotmail.com> wrote:
> I was wondering what the classes of amps really mean ? Could anyone
give me
> quick rundown ?
> Thanks,
> Tinker
>
>
transistor or tube ). If you really want to learn more about
amplifiers, get yourself a copy of "Sam's Radio Handbook" by William I.
Orr (W6SAI). It covers many other topics as well. Class A amps are the
most "Linear", but are inefficient, produce a lot of heat and are cost
prohibitive. Class C.....well, I won't even go there! Class AB offers
the best balance between "linearity" and efficiency and is the class
employed in most "top shelf" Amateur amplifiers today.
73.
LJ
Sent via Deja.com http://www.deja.com/
Share what you know. Learn what you don't.
little...@my-deja.com
"Toll Free" <toll...@bigradios.com> wrote:
>
> MR.2SC2879 <mwo...@aol.com2879> wrote in message
> news:19990920215039...@ng-fb1.aol.com...
> > class ab uses a push pull configuration
>
> You can run any class of operation in the push pull configuration.
The
> class of operation is independent of the design for push pull or
single
> ended.
>
biasing of the amplifying devices, not the "configuration".
Jack Thurston
No, they don't cover the entire
10 meter band!
10 meter band - 28.0 - 29.7
I don't think so........
Jack Thurston
They usually don't want to
"unkey" when they are oscillating
and generating vhf parasitics!
Bill Eitner
>
> If you like the Galaxy line, the 88 is about the best.
The 2950 is a better bang-for-the-buck choice that does
everything an 88 does for less except the TX audio effects.
The analog meter on the 88 is better than the bar graph on
the 2950 too. The TX audio effects and the analog meter
can be added to the 2950, but the features that the 2950
offers that aren't on the 88 can't be added to the 88
because the 2950 is CPU (central processing unit) controlled
while the 88 is not. To me, that makes the 2950 a better
choice.
> If you like the legal line of CB radios, then the Uniden 8719 chassis (148,
> Grant, etc.) are the best.
If it weren't for the Midland 79-290 I'd agree.
The 79-290 somehow slipped through the FCC cracks
(that should excite all the legal beagles on the
negwsgroup). The 79-290 has an FCC type-acceptance
number, therefore it's a legal CB. However, it's
a dual-final, high-level, AM modulated radio that
always does more than 4 watts AM (average) and 12
SSB (peak). The coarse clarifier is unlocked in
the stock configuration too. To add 5 extra bands
of frequencies all you have to do is solder jump two
points in the control head--you don't even have to
remove a single screw from the radio itself. The
coarse clarifier is already unlocked, so you'll
have full coverage. Remove Q33, tune one coil,
and adjust a few pots, and the radio will dead-key
2 and swing to 30+ and 35 on SSB at 14.5 volts.
The stability is excellent even when tuned-up.
That means the radio doesn't freak out when running
an amp into a high SWR or a mag-mount. The small
size and modern look will appeal to many people as
well. The price is good too, considering how cheap
the mods are. I'll completely set-up a 79-290 for
$40. Compare that to $90 or more to do a Grant or
a 148. The only thing that bothers people about
the 79-290 is that it needs a continuous power source
or it loses its memory. A number of people have
contacted Midland about that and were told that
it's normal. That can be an annoyance; but, all
things considered, the benefits of the 79-290
DEFINITELY outweigh the drawbacks. I've been in
CB for 20 years--I like the old standards like the
Grant and the 76. But, if I had to buy a new
"standard" CB right now, I'd buy a Midland 79-290.
> I typically see more Bird watts from a Cobra 148 than I do a Galaxy, but the
> Galaxy will do more on SSB clearly.
That's not what I see. Most Galaxies are dual
final radios--that means they naturally make
more power than the single-final standard CBs.
The AM-only Galaxies have audio output transformers.
That means they get the advantage of an autotransfromer
effect which raises their output to more than can be
had using a transistor-based modulator stage such
as is used on the 148. The 148/Grant chassis is
one of the weakest TX performers still in production,
in my opinion. They're the reason why amps like the
667 are still available. The 148/Grant is a throwback
to 20+ years ago when no CB radio made more than 15 to
18 peak watts. In those days even the AM-only radios
that had audio output transformers were weak because
they used such low-power RF driver and final transistors.
Maybe I misunderstood something.
> Toll Free
--
> Andrew Taylor <dre...@bellsouth.net> wrote in message
> news:37E8391F...@bellsouth.net...
> > O.K. I've read all that you and Toll Free have had to say about this.
> Texas Star
> > 500 is one of the best for someone like me who does not want to have to go
> out
> > and spend a lot of money on extra voltage, wiring and all that other good
> stuff.
> >
> > What would you pair this amp with. I've used Cobra's and Galaxy's but am
> open
> > for suggestions. I got out of CB'ing here in my local area because of all
> the
> > wild ones that tear up the channels but I sure have missed it and am
> considering
> > jumping back in.
> >
> > Last setup I had was the Galaxy 73V, Palamar 650, Wilson 1000 mag mount.
> Was
> > happy with it but I did have problems mentioned in previous post about amp
> not
> > wanting to unkey. {real pain in the ass to reach back and turn it off and
> back
> > on just to talk).
> >
> > > > >Tinker wrote:
> > > > >>
> > > > >> I was wondering what the classes of amps really mean ? Could anyone
> give
> > > > me
> > > > >> quick rundown ?
> > > > >> Thanks,
> > > > >> Tinker
> > > > >
> > > > >
Bill Eitner
I agree. What's worse is that the amp can't stand
that for very long and will fail. That results in
down time and an expensive repair.
Bill Eitner
>
> Yes, the Galaxy's will cover the entire 10 meter band down to 25 megs.
Boy, I didn't know that. I was going to recommend the
2950 or the Lincoln as I know they'll do the entire 10
meter band including the high end where alot of FM repeater
activity is starting to sprout up. Will the Galaxies do
offsets and PL tones? As far as I know, those things are
still the domain of the 2950.
Bill Eitner
> You mentioned class AB, how about class C, what can you volt these too
> comfortably?
>
> KRS
In almost all cases you can go 18 volts when the amp
is unbiased (technically Class C). 18 volts is the
C-E breakdown voltage for most 12 volt RF power
transistors. The amp's stability is much better
when unbiased (running in what's commonly refered to
as Class C). That allows you to get away with higher
supply voltages and AM drive levels. The top of the
transistor design curves are 16 volts; that's where
I would stop with a daily-use amp that might see bias
and/or hasn't been re-resonated for higher voltage use.
Bill Eitner
should feel blessed.
The problem is that you haven't added ANY leading edge information
to this newsgroup. If I'm wrong, tell me. List the leading edge
info and/or secrets that you've cut loose with since you've been
out here.
It's easy to bitch, criticize, and then list a bunch of callsigns
at the end in an attempt to make your opinions seem more qualified
than the next guy's. It's alot harder to prove that you're anything
more than just another average tech. A picture of you at a cluttered
bench isn't enough.
--
Hillbilly Dave wrote:
>
> all are good answers....some of these folks ain't the dumb ass's people
> think they are.....
>
> Dave
> KG5XR & WB5CYX (Club)
> EX- WB5LWZ , WN5DQG, WR5ALP
> ARMY MARS, AAT6YC
> KRH-4063/KRI-0332/KJO-8973
> (little voice of the Ozarks)
> Daves Radio Electronics
> Since 1972
> http://www.geocities.com/TheTropics/Island/4371/index.html
>
> <superiorw...@prodigy.net> wrote in message
> news:7s7gga$559u$1...@newssvr03-int.news.prodigy.com...
> >
> > Toll Free wrote: >>>you can volt these a little higher (But I don't
> > recommend more than 15.5
> > >volts.... 16 volts for a VERY short period of time), and you get a
> little
> > more out...
> >
> > You mentioned class AB, how about class C, what can you volt these too
> > comfortably?
> >
> > KRS
> >
> >
Bill Eitner
of amplification." I hope you get it.
--
Toll Free wrote:
>
> MR.2SC2879 <mwo...@aol.com2879> wrote in message
> news:19990920215039...@ng-fb1.aol.com...
> > class ab uses a push pull configuration
>
> You can run any class of operation in the push pull configuration. The
> class of operation is independent of the design for push pull or single
> ended.
>
Bill Eitner
Dig out your old books and review.
If you keep writing posts like this, you'll force me to jump in and
correct you--I don't want to do that. You, I and a couple of others
are the last of what I call "the old guard." We should be teaching,
not arguing amongst ourselves.
Bill Eitner
>
> I have a Silver Eagle 200 and was wondering what class amp it is?
It has no applied bias.
Since the transistors need .6 DC volts on their bases to
cause collector to emitter current to flow, and that the
.6 volts isn't supplied by an external bias circuit in
your amp, most people will call your amp a Class C amp.
In a semantic sense they're correct. In a realistic
sense, your amp trully operates just on the Class C side
of Class B--which is a LINEAR class. That's why it pro-
duces a useable SSB signal.
Chances are you're confused--that's not abnormal. VERY
few people on this newsgroup really know how to classify
amplifiers. Most who think they know are simply regurgi-
tating things they've heard or read by people they thought
were smart and/or infallible.
Toll Free
I retract my statement.
I was going by the current frequency spread, as well as the high end of an
old Pluto "H" model.
Had an extra 40 channels in their! ;-0
And you are also right, the Galaxy does not have any of the "goodies" that
the microprocessor controlled radios do, like offset.
If all you want to do is talk skip, the Galaxy will serve a person fine, in
my opinion.
Toll Free
Bill Eitner <kd6...@netzero.net> wrote in message
news:37EAB407...@netzero.net...
> Toll Free wrote:
> >
> > Yes, the Galaxy's will cover the entire 10 meter band down to 25 megs.
>
> Boy, I didn't know that. I was going to recommend the
> 2950 or the Lincoln as I know they'll do the entire 10
> meter band including the high end where alot of FM repeater
> activity is starting to sprout up. Will the Galaxies do
> offsets and PL tones? As far as I know, those things are
> still the domain of the 2950.
Toll Free
>
> The 2950 is a better bang-for-the-buck choice that does
> everything an 88 does for less except the TX audio effects.
> The analog meter on the 88 is better than the bar graph on
> the 2950 too. The TX audio effects and the analog meter
> can be added to the 2950, but the features that the 2950
> offers that aren't on the 88 can't be added to the 88
> because the 2950 is CPU (central processing unit) controlled
> while the 88 is not. To me, that makes the 2950 a better
> choice.
Their are a few personal things that I DON'T like about the 2950, nor the
88. I have one 88, but I don't run it.
I prefer my Uniden SSB chassis.
>
> > If you like the legal line of CB radios, then the Uniden 8719 chassis
(148,
> > Grant, etc.) are the best.
>
> If it weren't for the Midland 79-290 I'd agree.
Bill, I don't do this everyday. This is a new chassis to me, although I
have heard that the RX section sucks.
Sounds like a good radio. I would like to see one. Maybe when I am in
Oakland next weekend, I will stop by and look at it.
You near a BART station? I am going to be on the Ankle Express, but if you
are near a BART, I will stop by...
Anyway... I do like the 8719 chassis. I can see 10 watts Bird out of one
fairly easily, and rarely see that out of a Galaxy, even when really pumped.
The ones that mod a Galaxy for that many watts usually see a lot of them
brought back in a month or so. I also like the TX audio that comes from
one.
The transformer modulated radios where not in the equation because I was
talking SSB only. For AM use, any radio that uses a transformer for the
modulator works well.
>
> > I typically see more Bird watts from a Cobra 148 than I do a Galaxy, but
the
> > Galaxy will do more on SSB clearly.
See my statement above.
>
> That's not what I see. Most Galaxies are dual
> final radios--that means they naturally make
> more power than the single-final standard CBs.
Not necessarily! You ever look at the dual final Cybernet chassis? They
won't even hit 4 Bird watts! Shitty regulator design.
Galaxy is better, but I never see the even power application from the
modulator section from the 148.... Due in a large part to the better
voltage regulation of the Galaxy regulator / modulator. However, when a
"swing mod" is done to the Galaxy radio, it sounds like shit. Not so with
the 148.
> The AM-only Galaxies have audio output transformers.
> That means they get the advantage of an autotransfromer
> effect which raises their output to more than can be
> had using a transistor-based modulator stage such
> as is used on the 148.
I wasn't talking about the AM only chassis. If it was am only, then their
are a LOT better transmitters than the 148. For a dual mode radio, I still
like it.
The 148/Grant chassis is
> one of the weakest TX performers still in production,
> in my opinion. They're the reason why amps like the
> 667 are still available. The 148/Grant is a throwback
> to 20+ years ago when no CB radio made more than 15 to
> 18 peak watts. In those days even the AM-only radios
> that had audio output transformers were weak because
> they used such low-power RF driver and final transistors.
>
Guess we see things different. Both mentally, and on the meter. ;-0
Toll Free
Toll Free
If you measure base voltage / idling current on a typical diode bias amp,
the transistor is WAY on at 15 volts...
Too close for comfort for me, but I have people that do it and have gotten
away with it for years!
Toll Free
Bill Eitner <kd6...@netzero.net> wrote in message
news:37EAB706...@netzero.net...
> superiorw...@prodigy.net wrote:
>
> > You mentioned class AB, how about class C, what can you volt these too
> > comfortably?
> >
> > KRS
>
> In almost all cases you can go 18 volts when the amp
> is unbiased (technically Class C). 18 volts is the
> C-E breakdown voltage for most 12 volt RF power
> transistors. The amp's stability is much better
> when unbiased (running in what's commonly refered to
> as Class C). That allows you to get away with higher
> supply voltages and AM drive levels. The top of the
> transistor design curves are 16 volts; that's where
> I would stop with a daily-use amp that might see bias
> and/or hasn't been re-resonated for higher voltage use.
Bill Eitner
>
> > > If you like the Galaxy line, the 88 is about the best.
> >
> > The 2950 is a better bang-for-the-buck choice that does
> > everything an 88 does for less except the TX audio effects.
> > The analog meter on the 88 is better than the bar graph on
> > the 2950 too. The TX audio effects and the analog meter
> > can be added to the 2950, but the features that the 2950
> > offers that aren't on the 88 can't be added to the 88
> > because the 2950 is CPU (central processing unit) controlled
> > while the 88 is not. To me, that makes the 2950 a better
> > choice.
>
> Their are a few personal things that I DON'T like about the 2950, nor the
> 88. I have one 88, but I don't run it.
>
> I prefer my Uniden SSB chassis.
Okay, but when you consider the 88 and the 2950, the
2950 should come out on top.
> >
> > > If you like the legal line of CB radios, then the Uniden 8719 chassis
> (148,
> > > Grant, etc.) are the best.
> >
> > If it weren't for the Midland 79-290 I'd agree.
>
> Bill, I don't do this everyday. This is a new chassis to me, although I
> have heard that the RX section sucks.
I don't agree--especially when compared to the 2950.
> >
> > The 79-290 somehow slipped through the FCC cracks
> > (that should excite all the legal beagles on the
> > negwsgroup). The 79-290 has an FCC type-acceptance
> > number, therefore it's a legal CB. However, it's
> > a dual-final, high-level AM modulated radio that
> > always does more than 4 watts AM (average) and 12
> > SSB (peak). The coarse clarifier is unlocked in
> > the stock configuration too. To add 5 extra bands
> > of frequencies all you have to do is solder jump two
> > points in the control head--you don't even have to
> > remove a single screw from the radio itself. The
> > coarse clarifier is already unlocked, so you'll
> > have full coverage. Remove Q33, tune one coil,
> > adjust a few pots, and the radio will dead-key
> > 2 and swing to 30+ and 35 on SSB at 14.5 volts.
> > The stability is excellent even when tuned-up.
> > That means the radio doesn't freak out when running
> > an amp into a high SWR or a mag-mount. The small
> > size and modern look will appeal to many people as
> > well. The price is good too, considering how cheap
> > the mods are. I'll completely set-up a 79-290 for
> > $40. Compare that to $90 or more to do a Grant or
> > a 148. The only thing that bothers people about
> > the 79-290 is that it needs a continuous power source
> > or it loses its memory. A number of people have
> > contacted Midland about that and were told that
> > it's normal. That can be an annoyance; but, all
> > things considered, the benefits of the 79-290
> > DEFINITELY outweigh the drawbacks. I've been in
> > CB for 20 years--I like the old standards like the
> > Grant and the 76. But, if I had to buy a new
> > "standard" CB right now, I'd buy a Midland 79-290.
>
> Sounds like a good radio.
It is a good radio.
> I would like to see one.
You will eventually.
> Maybe when I am in
> Oakland next weekend, I will stop by and look at it.
>
> You near a BART station?
Nope. BART stops in the East bay; I'm in the West Bay.
> I am going to be on the Ankle Express, but if you
> are near a BART, I will stop by...
I wouldn't mind meeting you, but I don't know anything
about BART. Personally, I don't own a 79-290 either.
I'm still using my 2950 and backup President Jackson.
We'd have to go to a shop to see the 79-290.
> Anyway... I do like the 8719 chassis. I can see 10 watts Bird out of one
> fairly easily, and rarely see that out of a Galaxy, even when really pumped.
I never look for average wattage figures. Galaxies
always beat Grants/148s when it comes to peak power
on my bench. However, I've never seen 10 average
watts out of any single-final radio--even the AM-only
units.
> The ones that mod a Galaxy for that many watts usually see a lot of them
> brought back in a month or so. I also like the TX audio that comes from
> one.
I agree there. The TX audio from a Grant/148 looks alot
like the audio from a 76/29; it sounds louder and punchier
than a 2950 or a dual final Galaxy. However, I've never
compared it to a 79-290. What I've focused on is how nice
the 79-290 is on SSB. I take it for granted that the 79-290
will sound at least as good as a 2950 since its a high-level
AM modulated radio. That's good enough for me.
> The transformer modulated radios where not in the equation because I was
> talking SSB only. For AM use, any radio that uses a transformer for the
> modulator works well.
I agree; I just wanted to cover all bases.
> >
> > > I typically see more Bird watts from a Cobra 148 than I do a Galaxy, but
> the
> > > Galaxy will do more on SSB clearly.
>
> See my statement above.
>
> >
> > That's not what I see. Most Galaxies are dual
> > final radios--that means they naturally make
> > more power than the single-final standard CBs.
>
> Not necessarily! You ever look at the dual final Cybernet chassis? They
> won't even hit 4 Bird watts! Shitty regulator design.
Like I said, I look for peak power. Galaxies and
Superstars (Cybernet copies) always beat Grants/148s
in peak power. If they do that with a reasonable
waveform, it's guaranteed that the average power
will be at least comperable.
One of our discrepancies here is that I don't see
the Bird as being the last word in performance.
In the field or on the battleground you don't
have much choice. There, the Bird in CW
mode is the last word other than actual competition.
On a good test bench that isn't the case. Like
Dennis, I find that average (aka Bird) wattages
can be skewed by alot of factors. When a wattmeter
is all you've got, I recommend going with maximum
peak wattage rather than average wattage as a measure
of which is the more powerful unit.
> Galaxy is better, but I never see the even power application from the
> modulator section from the 148.... Due in a large part to the better
> voltage regulation of the Galaxy regulator / modulator. However, when a
> "swing mod" is done to the Galaxy radio, it sounds like shit. Not so with
> the 148.
We'd have to talk about this via e-mail as it doesn't
make sense to me. It sounds like you're trying to
baffle me with bullshit. The modulator stages are
of the same design in the Galaxies as in the 148s.
The only difference is that the active parts of the
Galaxies have to deal with twice as much power so
they're heavier.
> The 148/Grant chassis is
> > one of the weakest TX performers still in production,
> > in my opinion. They're the reason why amps like the
> > 667 are still available. The 148/Grant is a throwback
> > to 20+ years ago when no CB radio made more than 15 to
> > 18 peak watts. In those days even the AM-only radios
> > that had audio output transformers were weak because
> > they used such low-power RF driver and final transistors.
> >
>
> Guess we see things different. Both mentally, and on the meter. ;-0
I don't know what you mean by "mentally." Sounds
like more baffle with bullshit antics. The 8719
chassis has a good sound but weak numbers--it's
that simple. Anything else is bullshit--and you
know it. 18 peak watts is typical from a tuned-up
148. Any model Galaxy that was that weak wouldn't
stay in production for more than a couple of years.
> Toll Free
Toll Free
> > Their are a few personal things that I DON'T like about the 2950, nor
the
> > 88. I have one 88, but I don't run it.
> >
> > I prefer my Uniden SSB chassis.
>
> Okay, but when you consider the 88 and the 2950, the
> 2950 should come out on top.
Depends on the user. Overall, yes... For a moronic user, no. My
grandfather owns a 2900 RCI, and although it is a great radio, he much
prefers the ease of use of the Galaxy radios.... Can't stand to use the
VFO. This may be a moot point, since the 2950 has a "CB" mode, but still is
confusing to some operators.
It is a case by case basis, but on the upper end, you would be right.
> > Bill, I don't do this everyday. This is a new chassis to me, although I
> > have heard that the RX section sucks.
>
> I don't agree--especially when compared to the 2950.
Like I said.. I have yet to see the Midland...
The RCI was pretty easy to outdo in the RX section, though. Galaxy chassis
seem to be a little better tuned, but a "Channel Guard" type filter, or
another XTAL filter in line does help them, too.
But, if I had to buy a new
> > > "standard" CB right now, I'd buy a Midland 79-290.
> >
> > Sounds like a good radio.
>
> It is a good radio.
I have to take your word for it.
>
> > I would like to see one.
>
> You will eventually.
Maybe. I don't do this for a living, and I don't see much that isn't
dealing with competitions, so if the radio won't work well in a comp mobile,
I don't see it. I deal with either tube or strictly amateur equip. on the
base side....
I would be interested to see what the computer section of the radio did with
a linear of some power behind it. That is what I base the computer
controlled radios against... Because that is what is the biggest affect
that my operating standards have.. The Microprocessors have a hard time
with high RF field strength.
>
> > Maybe when I am in
> > Oakland next weekend, I will stop by and look at it.
> >
> > You near a BART station?
>
> Nope. BART stops in the East bay; I'm in the West Bay.
>
> > I am going to be on the Ankle Express, but if you
> > are near a BART, I will stop by...
>
> I wouldn't mind meeting you, but I don't know anything
> about BART. Personally, I don't own a 79-290 either.
> I'm still using my 2950 and backup President Jackson.
> We'd have to go to a shop to see the 79-290.
Too bad. Although if I get the position out their, I will be living in the
area! Guess that would make a meeting a little more accessible.
>
> > Anyway... I do like the 8719 chassis. I can see 10 watts Bird out of
one
> > fairly easily, and rarely see that out of a Galaxy, even when really
pumped.
>
> I never look for average wattage figures.
For an AM chassis, that is all I look at. For SSB, it is completely
useless. That is what the 4314 Bird is for.... Or the 43 with a PEP kit.
Galaxies
> always beat Grants/148s when it comes to peak power
> on my bench.
Mine, too. Typically a Galaxy stock will outtalk a 148 on SSB even when the
148 is peaked. They don't like to do more than 18 - 20 watts PEP, whereas
the Galaxy will outdo that stock.
Hats off to Galaxy for a good SSB transmitter.
However, I've never seen 10 average
> watts out of any single-final radio--even the AM-only
> units.
I can see 8 out of most any of the 8719 chassis. The Cobra 140 / Washington
was the easier TX section to get bigger numbers. The double conversion RX
chassis where a little tougher. I never digged deep enough to find out why,
but that was my findings.
>
> > The ones that mod a Galaxy for that many watts usually see a lot of them
> > brought back in a month or so. I also like the TX audio that comes from
> > one.
>
> I agree there. The TX audio from a Grant/148 looks alot
> like the audio from a 76/29; it sounds louder and punchier
> than a 2950 or a dual final Galaxy.
And on AM, that punch is usually what gets you heard. You forget, I operate
AM usually.... SSB is a sideline hobby.
However, I've never
> compared it to a 79-290. What I've focused on is how nice
> the 79-290 is on SSB. I take it for granted that the 79-290
> will sound at least as good as a 2950 since its a high-level
> AM modulated radio. That's good enough for me.
Then we really are looking at this from the same perspective... I look at
the AM transmitter. On SSB the Galaxy is a better choice, if you are mainly
an SSB operator. If most of my talking was basic AM, I would opt for the
Grant / 148 chassis, and I have. The 88 is sitting in a box behind me, and
the 148 is in my Suburban!
>
> > > > I typically see more Bird watts from a Cobra 148 than I do a Galaxy,
but
> > the
> > > > Galaxy will do more on SSB clearly.
> >
> > See my statement above.
> >
> > >
> > > That's not what I see. Most Galaxies are dual
> > > final radios--that means they naturally make
> > > more power than the single-final standard CBs.
Sean and Dennis went through this about a year ago. The higher AVG figures
usually do tend to carry the AM signal farther, but the higher PEP figures
do tend to make the SSB travel farther (as it should).
Granted, I can see 8 or 9 watts of carrier out of a Galaxy, but the needle
won't move when modulated, or you see a slight flicker backwards. What
would you rather see..... 9 watts, swinging to 6, or 3 watts swinging to 8?
> >
> > Not necessarily! You ever look at the dual final Cybernet chassis?
They
> > won't even hit 4 Bird watts! Shitty regulator design.
>
> Like I said, I look for peak power.
Their is our difference. I use the Bird, and although PEP on the Bird is
available, I don't always use it. It is nice to be able to see the total
picture, but if you are swinging backwards, and another station is going
forwards, the forward swinging station will be heard, all other things being
equal! The negative going power in the backward swinging radio will not
carry quite as far as one that swings forward.
Galaxies and
> Superstars (Cybernet copies) always beat Grants/148s
> in peak power.
Cybernet sucks all the way around.
Sorry, but that is my opinion as one that owned a shop. Cybernet had the
highest failure rate of any chassis at the time (now I would say that Maxon
carries that honor). Because of that, I stay with tried and true designs.
After all, what has worked for 20+ years must have something right!
If they do that with a reasonable
> waveform, it's guaranteed that the average power
> will be at least comperable.
Not necessarily!
I know that the 4CX250 tube will do 12Kw PEP, rated power. Pulsed.
The AVG output power is only 300 watts at that level.
My Pride DX-300 does 900 watts PEP.
It does the same 300 watts RMS.
Big difference, and the same holds true for the radio chassis. Although the
Galaxy doesn't use pulse power, it does not have the AM punch that the AM
only and 8719 chassis do!
>
> One of our discrepancies here is that I don't see
> the Bird as being the last word in performance.
I do, because that is the only people that I cater to. They don't care what
another "standard" says, as long as I can quote them a Bird reading, they
are happy!
> In the field or on the battleground you don't
> have much choice. There, the Bird in CW
> mode is the last word other than actual competition.
And usually, the Bird will tell you the same thing that the competition
will, all other things being equal!
> On a good test bench that isn't the case.
Your right. On a bench, with a peak reading meter, the Galaxy will blow
most any other chassis out of the water. I agree on that. However, I don't
do the majority of my broadcasting into my dummy load....
Like
> Dennis, I find that average (aka Bird) wattages
> can be skewed by alot of factors.
As can any other wattmeter on the market!
When a wattmeter
> is all you've got, I recommend going with maximum
> peak wattage rather than average wattage as a measure
> of which is the more powerful unit.
Actual competition will tell you different! That is where you and I differ.
I deal with competition on (almost) a daily basis.... That is what I
purchase my radio for...
That, and to give local information to any trucker that needs it! ;-0
>
> > Galaxy is better, but I never see the even power application from the
> > modulator section from the 148.... Due in a large part to the better
> > voltage regulation of the Galaxy regulator / modulator. However, when a
> > "swing mod" is done to the Galaxy radio, it sounds like shit. Not so
with
> > the 148.
>
> We'd have to talk about this via e-mail as it doesn't
> make sense to me. It sounds like you're trying to
> baffle me with bullshit. The modulator stages are
> of the same design in the Galaxies as in the 148s.
> The only difference is that the active parts of the
> Galaxies have to deal with twice as much power so
> they're heavier.
And gain figures on the modulator transistor is different, the biasing is
different. I will say that for the average radio, the Galaxy has a better
modulator. Set your carrier, and that is the number you see on the Bird.
It has a lot tighter regulator (modulator) section.
Doesn't change the fact that you can take a 148 down to a half watt carrier,
and let it swing wildly from their, and it is completely understandable.
Do that with a Galaxy! Makes the chassis damn near non-understandable! I
know. I have to set these radios up for competition use, and I don't run
GARGANTUAN carriers!
> >
> > Guess we see things different. Both mentally, and on the meter. ;-0
>
> I don't know what you mean by "mentally."
What do I mean... I mean that I like seeing higher avg power, you like
higher PEP. I like the old chassis, you like the new.
Nothing wrong with either of us, because we use our radios for different
purposes. For your applications, I agree, the Galaxy (RCI) chassis is
better.
For the AM use, and occasional SSB, the 148 chassis is a better radio. It
is time proven, works well at any carrier level, sounds good at any carrier
level and lasts even after it has been abused all day long.
You can't say the same thing about a Galaxy!
On SSB, though, the Galaxy will eat a 148 for lunch!
Sounds
> like more baffle with bullshit antics.
No, not at all.
The 8719
> chassis has a good sound but weak numbers--it's
> that simple.
That is what an amplifier is built for. Numbers. If you have garbage going
in, garbage goes out.
Anything else is bullshit--and you
> know it. 18 peak watts is typical from a tuned-up
> 148.
Yes, but the avg numbers are a lot higher than an equivelant "other brand".
Any model Galaxy that was that weak wouldn't
> stay in production for more than a couple of years.
Your right again! But, those are radios that have a purpose. Just like the
148s.
You can get an equivelant 148 radio with a Galaxy faceplate for nearly the
same price... No freq counter, etc.... If the 148 was such an outdated
piece of shit, wouldn't word be out by now about it? I mean... Why do they
still make it?
>
Later.
Toll Free
Bill Eitner
>
> > > Their are a few personal things that I DON'T like about the 2950, nor
> the
> > > 88. I have one 88, but I don't run it.
> > >
> > > I prefer my Uniden SSB chassis.
> >
> > Okay, but when you consider the 88 and the 2950, the
> > 2950 should come out on top.
>
> Depends on the user. Overall, yes... For a moronic user, no. My
> grandfather owns a 2900 RCI, and although it is a great radio, he much
> prefers the ease of use of the Galaxy radios.... Can't stand to use the
> VFO. This may be a moot point, since the 2950 has a "CB" mode, but still is
> confusing to some operators.
A "moronic" point is exactly what it is. The 2950 in the CB
mode is EASIER to run than a CB because it outlines the RC ("A")
channels. In other posts I've said that the 2950 can be inti-
midating, but that's only until the owner reads the owners
manual or has a helpful dealer go through it with him.
> It is a case by case basis, but on the upper end, you would be right.
Okay.
> > > Bill, I don't do this everyday. This is a new chassis to me, although I
> > > have heard that the RX section sucks.
> >
> > I don't agree--especially when compared to the 2950.
>
> Like I said.. I have yet to see the Midland...
>
> The RCI was pretty easy to outdo in the RX section, though. Galaxy chassis
> seem to be a little better tuned, but a "Channel Guard" type filter, or
> another XTAL filter in line does help them, too.
The thing to remember is that the 2950 is still as
sensitive as any other--it's just not as selective (quiet).
In other words, it's not like you're going to hear things
on other radios that you won't hear on a 2950. The
difference is that there's more hiss noise in with the
signal when received on a 2950.
I use a 2950 as my base/bench radio. Not long ago I
got tired of hearing the bullshit and conducted my own
test to see just how bad the 2950 receiver was. I had
a 138XLR on my bench. Many on this newgroup think that
chassis has one of the best receivers ever made.
Personally, I don't agree. The UPd 858 chassis that
includes the 139 is a single conversion receiver with
a fancy filter. I've done all the common receiver mods
to my 2950. Both the 139 and my 2950 were in peak tune.
The 139 was quieter, but there were weak signals that I
just plain couldn't hear (I couldn't make out the words
the person was saying) on the 139 that I could (I could
hear the words) on my 2950. I don't like how noisy the
2950 receiver is. They could've used some FETs and
quieted it down; but, in my opinion, it's no less
sensitive than the coveted late 858 chassis.
--
> But, if I had to buy a new
> > > > "standard" CB right now, I'd buy a Midland 79-290.
> > >
> > > Sounds like a good radio.
> >
> > It is a good radio.
>
> I have to take your word for it.
Can't you simply agree with me?
> >
> > > I would like to see one.
> >
> > You will eventually.
>
> Maybe. I don't do this for a living, and I don't see much that isn't
> dealing with competitions, so if the radio won't work well in a comp mobile,
> I don't see it. I deal with either tube or strictly amateur equip. on the
> base side....
Then take some time to go play with one.
It's not a perfect radio in every way, but
it's a great radio for the money. It's like
taking the PC-122 to the next level.
> I would be interested to see what the computer section of the radio did with
> a linear of some power behind it. That is what I base the computer
> controlled radios against... Because that is what is the biggest affect
> that my operating standards have.. The Microprocessors have a hard time
> with high RF field strength.
I only have experience with them up to the 500
watt PEP level. At that level the radio doesn't
even know anything unusual is going on.
> >
> > > Maybe when I am in
> > > Oakland next weekend, I will stop by and look at it.
> > >
> > > You near a BART station?
> >
> > Nope. BART stops in the East bay; I'm in the West Bay.
> >
> > > I am going to be on the Ankle Express, but if you
> > > are near a BART, I will stop by...
> >
> > I wouldn't mind meeting you, but I don't know anything
> > about BART. Personally, I don't own a 79-290 either.
> > I'm still using my 2950 and backup President Jackson.
> > We'd have to go to a shop to see the 79-290.
>
> Too bad. Although if I get the position out their, I will be living in the
> area! Guess that would make a meeting a little more accessible.
Across the bay is only 20 road miles. If you're
really there I'll show up. On the other hand,
the same goes for you. Once you get a car, come
see me. Seeing my shop may be of more value to
you than seeing my face.
> > > Anyway... I do like the 8719 chassis. I can see 10 watts Bird out of
> one
> > > fairly easily, and rarely see that out of a Galaxy, even when really
> pumped.
> >
> > I never look for average wattage figures.
>
> For an AM chassis, that is all I look at. For SSB, it is completely
> useless. That is what the 4314 Bird is for.... Or the 43 with a PEP kit.
>
> Galaxies
> > always beat Grants/148s when it comes to peak power
> > on my bench.
>
> Mine, too. Typically a Galaxy stock will outtalk a 148 on SSB even when the
> 148 is peaked. They don't like to do more than 18 - 20 watts PEP, whereas
> the Galaxy will outdo that stock.
>
> Hats off to Galaxy for a good SSB transmitter.
>
> However, I've never seen 10 average
> > watts out of any single-final radio--even the AM-only
> > units.
>
> I can see 8 out of most any of the 8719 chassis. The Cobra 140 / Washington
> was the easier TX section to get bigger numbers. The double conversion RX
> chassis where a little tougher. I never digged deep enough to find out why,
> but that was my findings.
6 to 8 is one thing, but 10 is a BIG another.
> >
> > > The ones that mod a Galaxy for that many watts usually see a lot of them
> > > brought back in a month or so. I also like the TX audio that comes from
> > > one.
> >
> > I agree there. The TX audio from a Grant/148 looks alot
> > like the audio from a 76/29; it sounds louder and punchier
> > than a 2950 or a dual final Galaxy.
>
> And on AM, that punch is usually what gets you heard. You forget, I operate
> AM usually.... SSB is a sideline hobby.
I'd put up a dual final radio against a 148 and win
every time in a competition even though I didn't
sound as loud.
> However, I've never
> > compared it to a 79-290. What I've focused on is how nice
> > the 79-290 is on SSB. I take it for granted that the 79-290
> > will sound at least as good as a 2950 since its a high-level
> > AM modulated radio. That's good enough for me.
>
> Then we really are looking at this from the same perspective... I look at
> the AM transmitter. On SSB the Galaxy is a better choice, if you are mainly
> an SSB operator. If most of my talking was basic AM, I would opt for the
> Grant / 148 chassis, and I have. The 88 is sitting in a box behind me, and
> the 148 is in my Suburban!
Given what you've said, we aren't looking at this from
the same perspective. In my view it takes an AM-only
standard to beat a dual-final in competition. In other
words, my 2950 won't sound as punchy but it'll beat
your 148 every time.
> >
> > > > > I typically see more Bird watts from a Cobra 148 than I do a Galaxy,
> but
> > > the
> > > > > Galaxy will do more on SSB clearly.
> > >
> > > See my statement above.
> > >
> > > >
> > > > That's not what I see. Most Galaxies are dual
> > > > final radios--that means they naturally make
> > > > more power than the single-final standard CBs.
>
> Sean and Dennis went through this about a year ago. The higher AVG figures
> usually do tend to carry the AM signal farther, but the higher PEP figures
> do tend to make the SSB travel farther (as it should).
I don't know what that means. Real dual final radios show higher
average AND peak numbers. I never heard Sean or Dennis say a 148
carried higher AM average wattages than a dual final radio. For
me to believe that you'll have to pull up a quote. My personal
experience says no to that--what else can I go with? I remember
Sean saying his personal mobile radio was a 2950--not a 148--even
though he could have anything he wanted. Logic tells me that if
a 148 was better than a 2950 that's what Sean would be using.
> Granted, I can see 8 or 9 watts of carrier out of a Galaxy, but the needle
> won't move when modulated, or you see a slight flicker backwards. What
> would you rather see..... 9 watts, swinging to 6, or 3 watts swinging to 8?
Given your conditions, there's very little difference.
Both will hold steady at 6. Like you've seen, my 2950
will hold an 8 watt carrier on a Bird. On a 148 the
needle would swing back to 6 and a half. I'm not a dummy.
I've been at this for 20 years. I know what 148s and 2950s
do. A perfectly well-tuned 2950 won't backswing even when
forced to hold a 10 watt dead-key assuming it's DC supply
is adequate. NO 148 could ever hold a 10 watt dead-key
without backswinging on a Bird.
> > >
> > > Not necessarily! You ever look at the dual final Cybernet chassis?
> They
> > > won't even hit 4 Bird watts! Shitty regulator design.
> >
> > Like I said, I look for peak power.
>
> Their is our difference. I use the Bird, and although PEP on the Bird is
> available, I don't always use it. It is nice to be able to see the total
> picture, but if you are swinging backwards, and another station is going
> forwards, the forward swinging station will be heard, all other things being
> equal!
How do you ever know when that's happening? And who's
to say that's really the truth? I can just as easily say
that the station with higher peak power is the one being
heard. Today, modulator kits are everywhere. They skew
the classic, average Bird assumtion. Dennis tried to
teach us that long ago. I accepted it--you obviously
haven't. Peak power readings are the only truth left
to us--get used to it.
> Galaxies and
> > Superstars (Cybernet copies) always beat Grants/148s
> > in peak power.
>
> Cybernet sucks all the way around.
That's a biased, personal opinion based on nothing
of substance.
> Sorry, but that is my opinion as one that owned a shop.
Again, so what?
> Cybernet had the
> highest failure rate of any chassis at the time (now I would say that Maxon
> carries that honor).
Not in the old days. Only when the copies became
prevalent. Think about it. Midlands, road talkers,
and Penney's radios were and are every bit as good
as their uniden counterparts.
> Because of that, I stay with tried and true designs.
> After all, what has worked for 20+ years must have something right!
That's bullshit. Uniden survived--that doesn't
make their stuff better by proxy. If Cybernet
evolved like Uniden evolved, who's to say Cybernet
wouldn't be better?
Personally, I think alot of the "export" designs
are as much Cybernet copies as they are Uniden
copies. Look at the trace paths on the left
side of the solder side of the board on all
Superstars and Galaxies as well as their
new copies like Northstar. The board design
looks much more like a Cybernet than a Uniden
design. At the very least, somebody is stealing
the old Cybernet board layouts. What's to say
they aren't stealing the circuit designs as well?
You need to look at this objectively.
> If they do that with a reasonable
> > waveform, it's guaranteed that the average power
> > will be at least comperable.
>
> Not necessarily!
Yes, necessarily.
> I know that the 4CX250 tube will do 12Kw PEP, rated power. Pulsed.
Pulsed power is bullshit when compared to CB.
> The AVG output power is only 300 watts at that level.
>
> My Pride DX-300 does 900 watts PEP.
>
> It does the same 300 watts RMS.
>
> Big difference, and the same holds true for the radio chassis. Although the
> Galaxy doesn't use pulse power, it does not have the AM punch that the AM
> only and 8719 chassis do!
That's crap. If that were the case they (Galaxy) wouldn't
be sucessful. The majority of bucks-up CBers use Galaxy
radios because they're known performers.
The first thing you need to straighten out is the output
out of that DX3. It should hold that 300 watt carrier and
then some resulting in a much higher peak value.
> >
> > One of our discrepancies here is that I don't see
> > the Bird as being the last word in performance.
>
> I do, because that is the only people that I cater to. They don't care what
> another "standard" says, as long as I can quote them a Bird reading, they
> are happy!
Still, we both know that doesn't mean anything.
> > In the field or on the battleground you don't
> > have much choice. There, the Bird in CW
> > mode is the last word other than actual competition.
>
> And usually, the Bird will tell you the same thing that the competition
> will, all other things being equal!
All other things are NEVER equal.
> > On a good test bench that isn't the case.
>
> Your right. On a bench, with a peak reading meter, the Galaxy will blow
> most any other chassis out of the water. I agree on that. However, I don't
> do the majority of my broadcasting into my dummy load....
What difference does it make? A dummy load makes
other factors become equal. You should like that.
I have to say that sustainable peak rules.
> Like
> > Dennis, I find that average (aka Bird) wattages
> > can be skewed by alot of factors.
>
> As can any other wattmeter on the market!
You're using a Bird--we KNOW that thing can go
all over the place--at least admit that. Average
Bird readings are even a bigger joke.
> When a wattmeter
> > is all you've got, I recommend going with maximum
> > peak wattage rather than average wattage as a measure
> > of which is the more powerful unit.
>
> Actual competition will tell you different! That is where you and I differ.
> I deal with competition on (almost) a daily basis.... That is what I
> purchase my radio for...
>
> That, and to give local information to any trucker that needs it! ;-0
If my 2950 were to beat your 148, what would you say then?
I trully believe that would be the case. If you intend to
live here and talk like a big shot, we'll have to clash.
> >
> > > Galaxy is better, but I never see the even power application from the
> > > modulator section from the 148.... Due in a large part to the better
> > > voltage regulation of the Galaxy regulator / modulator. However, when a
> > > "swing mod" is done to the Galaxy radio, it sounds like shit. Not so
> with
> > > the 148.
> >
> > We'd have to talk about this via e-mail as it doesn't
> > make sense to me. It sounds like you're trying to
> > baffle me with bullshit. The modulator stages are
> > of the same design in the Galaxies as in the 148s.
> > The only difference is that the active parts of the
> > Galaxies have to deal with twice as much power so
> > they're heavier.
>
> And gain figures on the modulator transistor is different, the biasing is
> different. I will say that for the average radio, the Galaxy has a better
> modulator. Set your carrier, and that is the number you see on the Bird.
> It has a lot tighter regulator (modulator) section.
That goes for a 148 too. What't the difference?
> Doesn't change the fact that you can take a 148 down to a half watt carrier,
> and let it swing wildly from their, and it is completely understandable.
>
> Do that with a Galaxy! Makes the chassis damn near non-understandable! I
> know. I have to set these radios up for competition use, and I don't run
> GARGANTUAN carriers!
I disagree. Again. you talk like you're moving in here.
We'll see. You'll have to deal with me and Prime Minister.
You talk the talk, but I don't think your walk works.
> > >
> > > Guess we see things different. Both mentally, and on the meter. ;-0
> >
> > I don't know what you mean by "mentally."
>
> What do I mean... I mean that I like seeing higher avg power, you like
> higher PEP. I like the old chassis, you like the new.
What makes that "mental?" You're talking meter readings.
I want to get along with you, but you can't bully me. Maybe
you should call me when you get close.
> Nothing wrong with either of us, because we use our radios for different
> purposes. For your applications, I agree, the Galaxy (RCI) chassis is
> better.
It's a little late in the game for that.
> For the AM use, and occasional SSB, the 148 chassis is a better radio. It
> is time proven, works well at any carrier level, sounds good at any carrier
> level and lasts even after it has been abused all day long.
That's simply crap.
> You can't say the same thing about a Galaxy!
Yes I can, and I already have. My 2950 will
support a 10 watt carrier at 14.5 volts.
Show me the nearly stock 148 that will do that.
> On SSB, though, the Galaxy will eat a 148 for lunch!
The 2950/Galaxies will eat 148s in any mode--
that's what they're made to do and that's why
they're popular.
> Sounds
> > like more baffle with bullshit antics.
>
> No, not at all.
I believe you're being genuine, but your
arguments don't work.
> The 8719
> > chassis has a good sound but weak numbers--it's
> > that simple.
>
> That is what an amplifier is built for. Numbers. If you have garbage going
> in, garbage goes out.
That's true to a point, but we're not talking
about amps--we're talking about radios.
If you want to talk amps, I really believe
in the straight 4-pill design. I believe
the straight 4 to be the most popular design
in production today because of how the radios
work. The straight 4s are a perfect match to
the 30-35 watt PEP radios that are very popular
today. That doesn't include the weak-ass 148.
> Anything else is bullshit--and you
> > know it. 18 peak watts is typical from a tuned-up
> > 148.
>
> Yes, but the avg numbers are a lot higher than an equivelant "other brand".
Using a sinusoidal waveform, 18 peak watts
means the underlying carrier was no more
than 6 watts. That also holds true for
average Bird watts.
> Any model Galaxy that was that weak wouldn't
> > stay in production for more than a couple of years.
>
> Your right again! But, those are radios that have a purpose. Just like the
> 148s.
>
> You can get an equivelant 148 radio with a Galaxy faceplate for nearly the
> same price... No freq counter, etc.... If the 148 was such an outdated
> piece of shit, wouldn't word be out by now about it? I mean... Why do they
> still make it?
The word is out on it. I had one that was fully modified
and it took me 6 months to sell it because they're just
not as popular as they used to be. It was a sound-tracker
too. People know that they're weak compared to today's
radios. They just don't want them anymore.
> Later.
Dave Hall
>
> Toll Free wrote:
> >
> > Yes, the Galaxy's will cover the entire 10 meter band down to 25 megs.
>
> 2950 or the Lincoln as I know they'll do the entire 10
> meter band including the high end where alot of FM repeater
> activity is starting to sprout up. Will the Galaxies do
> offsets and PL tones? As far as I know, those things are
> still the domain of the 2950.
The 2950 does PL tones? Since when? I know mine doesn't. All mine has is
a stupid roger beep. It does do splits quite nicely though.
The Uniden HR-2600 DOES do PL tones and repeater splits, which was its
advantage (for a 10 meter FM ham) over the 2510. For the Cber, the 2510
was a better choice.
FWIW, I've never seen a galaxy radio that I really liked. Most of them
sound crappy on SSB, especially after they've been "done up" by Joe
screwdriver. Their frequency drifts, the built-in counter generates hash
noise on some models, and I've seen some that the final stage self
oscillates. Not the kind of radio that I would own......
I still like the 2510 as the 10 meter radio of choice, and the Uniden
8719 chassis for "legal" CB, although that Midland model sounds very
interesting.......
Dave
"Sandbagger"
Dave
"Sandbagger"
LDD7777
only a 76 will out talk any of those junk radio's and last a hell of alot
longer.2950's fall apart and short out in most truck setups.Good for a base
unit but not year round in a car or truck.Galaxies sounds good but have alot of
RX problems and poor solder joints.SSB go with a Grant xl /148.Sean Told
everybody out here a while back the 76 put up the best numbers.Go to a keydown
and see what people use for radio's. That will give you an idea of the radio's
that give the best peak watts and audio.Hint: not to many 2950's or
galaxie's.1200........```!```
Bill Eitner
> The 2950 does PL tones? Since when? I know mine doesn't. All mine has is
> a stupid roger beep. It does do splits quite nicely though.
Supposedly they will after you add the optional
add-on board. I've never ordered, obtained, or
installed one, so don't ask. All I know is that
it's supposed to be available.
> Dave
> "Sandbagger"
Bill Eitner
>
> Bill are you losing it?
Not at all.
> You are picking a 2950 and a galaxie over a uniden?
When it comes to covering all of the 10 meter
band and having CPU generated features--yes
I prefer the 2950. For over 10 years it's
been the best value in CB/10 meter radios.
> AM
> only a 76 will out talk any of those junk radio's and last a hell of alot
> longer.
You didn't read the whole post. AM isn't all
there is to CB/10 meters. The 76 is a simple
radio with an audio output transformer instead
of a transistor based modulator--those are the
reasons for it ruggedness and performance. On
the other hand, it's a simpleton's radio that
quickly becomes boring if you're into anything
other than competition or banging heads with
the AM idiots.
> 2950's fall apart and short out in most truck setups.
There's a million of them in service. Less
than 1 percent have problems, but closed-minded
people only remember the bad stories they've heard.
> Good for a base
> unit but not year round in a car or truck.
See above.
> Galaxies sounds good but have alot of
> RX problems and poor solder joints.SSB go with a Grant xl /148.Sean Told
> everybody out here a while back the 76 put up the best numbers.
Sean runs a 2950 in his car. Only in competition
do you need the "best numbers." And look at Sean;
he doesn't even have time to get out here anymore
because he's busting his ass honoring the unrealistic
warranty he put on all the radios he tuned up in the
past. He's far from being all-knowing.
> Go to a keydown
> and see what people use for radio's. That will give you an idea of the radio's
> that give the best peak watts and audio.Hint: not to many 2950's or
> galaxie's.1200........```!```
AM and competition isn't all there is to CB.
You're narrow minded.
Enjoy your 76 since you're so anal that you'll never
be able to enjoy anything else.
Bill Eitner
>
> Sorry Bill i don't want to piss you off or anything .
You didn't. I just noticed your post. If I
see a post like that I won't let it slide--
would you? Nobody likes getting slammed.
> Just want to tell it the
> way it is .
It's only the way it is in your mind.
I've owned six 2950s since I learned of them in '88.
I've only had to repair 1 of them. The others
were sold to people that liked my sound. I still
use one and back it up with a President Jackson
just in case all the horrible and frequent failures
begin. That hasn't happened yet.
> I live in the northeast and the 2950's don't stay together up
> here.Between the cold winters and bumps in the roads the 2950 goes south real
> quick.
Maybe you've just been unlucky or you're going by
other people's horror stories. The main board
design in a 2950 is basically the same as in the
old export Uniden Grant--which isn't a helluva
lot different than a standard Grant. The CPU
section can be sensitive, but they've improved
that over time too. The latest generation
(serial numbers above 440000) are alot less
parts dense than the earlier ones. That adds
up to greater reliability.
I just don't have a problem with them. It takes
all kinds out here. There is no one, unarguable
truth out here. Thinking there is will just
lead to arguments.
> If you want channels the hr 2510 last longer(uniden).
I had a Lincoln when I discovered the 2950.
I couldn't get rid of the Lincoln quick enough.
I think the 2510 and it's clones are crude
radios. They especially suck when it comes to
AM modulation.
> By the way i run a
> uniden GRANT XL and a nice Washington with most of advantages of the exports
> ,which will out live your fine 2950.
In your opinion.
Grants and Washingtons are 20+ year old designs
that are barely any more advanced than the 76.
Simple radios for simple people.
> Take care Bill. Just my two cents .
73.
EMO
with it in 10 yrs
Bill Eitner wrote in message <37EC368A...@netzero.net>...
LDD7777
way it is .I live in the northeast and the 2950's don't stay together up
here.Between the cold winters and bumps in the roads the 2950 goes south real
uniden GRANT XL and a nice Washington with most of advantages of the exports
Bill Eitner
>
> my mom has a early 2950 old and lives in upstate ny she has not had a prob
> with it in 10 yrs
There are hundreds of thousands more like that too.
Nearly a million have been produced. A 2% failure
rate means 20,000 of them have failed. The failures
are what stick in people's minds. The ones that
just work and work and work even when heavily modified
are taken for granted.
NONE of today's radios are 100% reliable. They can't
be made bulletproof and still be competatively priced.
Smart people realize that and keep a backup radio on
hand. They also keep backup mics and antennas on hand.
Then, when (not if) something fails, it's not a big deal.
The people that bitch the most about a failed radio are
the ones that had to do without while it was being repaired.
--
> Bill Eitner wrote in message <37EC368A...@netzero.net>...
> >LDD7777 wrote:
> >>
> >> Sorry Bill i don't want to piss you off or anything .
> >
> > You didn't. I just noticed your post. If I
> > see a post like that I won't let it slide--
> > would you? Nobody likes getting slammed.
> >
> >> Just want to tell it the
> >> way it is .
> >
> > It's only the way it is in your mind.
> >
> > I've owned six 2950s since I learned of them in '88.
> > I've only had to repair 1 of them. The others
> > were sold to people that liked my sound. I still
> > use one and back it up with a President Jackson
> > just in case all the horrible and frequent failures
> > begin. That hasn't happened yet.
> >
> >> I live in the northeast and the 2950's don't stay together up
> >> here.Between the cold winters and bumps in the roads the 2950 goes south
> real
> >> quick.
> >
> > Maybe you've just been unlucky or you're going by
> > other people's horror stories. The main board
> > design in a 2950 is basically the same as in the
> > old export Uniden Grant--which isn't a helluva
> > lot different than a standard Grant. The CPU
> > section can be sensitive, but they've improved
> > that over time too. The latest generation
> > (serial numbers above 440000) are alot less
> > parts dense than the earlier ones. That adds
> > up to greater reliability.
> >
> > I just don't have a problem with them. It takes
> > all kinds out here. There is no one, unarguable
> > truth out here. Thinking there is will just
> > lead to arguments.
> >
> >> If you want channels the hr 2510 last longer(uniden).
> >
> > I had a Lincoln when I discovered the 2950.
> > I couldn't get rid of the Lincoln quick enough.
> > I think the 2510 and it's clones are crude
> > radios. They especially suck when it comes to
> > AM modulation.
> >
> >> By the way i run a
> >> uniden GRANT XL and a nice Washington with most of advantages of the
> exports
> >> ,which will out live your fine 2950.
> >
> > In your opinion.
> >
> > Grants and Washingtons are 20+ year old designs
> > that are barely any more advanced than the 76.
> >
> > Simple radios for simple people.
> >
> >> Take care Bill. Just my two cents .
> >
Toll Free
Toll Free
MR.2SC2879 <mwo...@aol.com2879> wrote in message
news:19990925224012...@ng-cj1.aol.com...
> you know copy right laws are there for a reason so maby you should start
using
> quotes. see you in lubbock toll bitch
> <<<<<<<<MR.2879>>>>>>>>
MR.2SC2879
Dave Hall
>
> Dave Hall wrote:
>
> > The 2950 does PL tones? Since when? I know mine doesn't. All mine has is
> > a stupid roger beep. It does do splits quite nicely though.
>
> Supposedly they will after you add the optional
> add-on board. I've never ordered, obtained, or
> installed one, so don't ask. All I know is that
> it's supposed to be available.
>
Oh, and add-on extra. That's different. Yea, and you can also add a
speech compressor too, as an add-on.
Any radio can do PL tones, with the addition of a PL encoder board, such
as a Com-Spec unit.
Dave
"Sandbagger"
Dave Hall
Two things. First, I've seen more of my share of bad 2950's. That being
said, most of the problems with the 2950 revolve around cold solder
joints on the chassis mount regulators.
I run a 2950 in my truck. I've had it for 7 or 8 years now. I've taken
care of the solder joint problems, and other than that, the rig has
performed flawlessly. It does have a poor noise blanker, and the
adjacent channel rejection is less than some other radios like a Uniden
Grant. But I rarely find myself in a situation where bleedover is a
problem.
>
> > If you want channels the hr 2510 last longer(uniden).
>
> I had a Lincoln when I discovered the 2950.
> I couldn't get rid of the Lincoln quick enough.
> I think the 2510 and it's clones are crude
> radios. They especially suck when it comes to
> AM modulation.
I find the audio of the 2510 to be just fine. You just have to keep the
carrier level to less than 15 watts, and you'll be ok. On the scope, you
cannot tell the difference between the 2510's low level modulation, and
that of another radio with high level modulation.
The one thing that you do have to be careful of with a 2510 (and the
President Jackson, which has virtually the same transmitter) is the
power control circuit. The power control derives it's feedback from an
SWR sensing diode, which allows the transmitter to back down the power
when the SWR gets high, thereby saving the final. But an unpleasent side
effect of this circuit is that under certain conditions, (such as the
input matching of a amplifier) the feedback can be greatly reduced which
results in the rig putting out too much power. This can cause overdrive
of the amplifier, and the distorted sound you get when you have no
forward swing and all back swing.
Dave
"Sandbagger"
Toll Free
The only type of protection that they have is overheat, and that is done
through a simple thermister.
The problem that you are seeing is because of a higher than what is called
for input impedance on cheaper or bad amplifiers.
A transmitter will put out 4 watts into a 50 ohm load...
It will not put out 4 watts into a 75 ohm load (way less, as a matter of
fact, and this is a 2 to 1 swr).
Consequently, when driven into a 40 or 30 ohm load, the SWR goes up, but
their is more current in the feedline to the box, resulting in greater
drive!
Toll Free
Dave Hall <nojunkma...@worldlynx.net> wrote in message
news:37F0BF...@worldlynx.net...
Bill Eitner
> Two things. First, I've seen more of my share of bad 2950's. That being
> said, most of the problems with the 2950 revolve around cold solder
> joints on the chassis mount regulators.
I agree. The regulator fix is easy and common knowledge
these days.
> I run a 2950 in my truck. I've had it for 7 or 8 years now. I've taken
> care of the solder joint problems, and other than that, the rig has
> performed flawlessly. It does have a poor noise blanker, and the
> adjacent channel rejection is less than some other radios like a Uniden
> Grant. But I rarely find myself in a situation where bleedover is a
> problem.
Again, I agree. The meter is lousy too.
> >
> > > If you want channels the hr 2510 last longer(uniden).
> >
> > I had a Lincoln when I discovered the 2950.
> > I couldn't get rid of the Lincoln quick enough.
> > I think the 2510 and it's clones are crude
> > radios. They especially suck when it comes to
> > AM modulation.
>
> I find the audio of the 2510 to be just fine. You just have to keep the
> carrier level to less than 15 watts, and you'll be ok. On the scope, you
> cannot tell the difference between the 2510's low level modulation, and
> that of another radio with high level modulation.
Here, I disagree. In my experience, you have to
lower the carrier to 5 watts before you'll see
100% positive modulation on a scope. The modulation
envelope peaks are alot more rounded too. The
waveform doesn't look like a textbook AM modulation
envelope at all. You can see the effect of the
linear stages that the signal has been put through.
Comparing tuned-up radios, the diffierence between a
2510 and a 2950 on AM using a scope or a monitor receiver
is very clear. The only way to make a 2510 even
come close is to reduce the carrier to the point
where the maximum peak power begins to drop. That
happens in the 4 to 5 watt range. At that point,
you've got all the positive modultion you're going
to get. The sound isn't too terribly bad, but the
high-level AM "bark" just isn't there. I don't
like the fact that you lose peak power when you
lower the carrier below about 5 watts either.
That compromises the performance when using CB
amps that show symptoms of overdrive if the carrier
is above 2 to 2.5 watts.
On the other hand, the 2510 will show higher peak
power output with a simple tune-up on SSB than a
2950. They have a nice, stable SSB sound too.
If a guy could handle the lower tech CPU with its
lack of features, and is only interested in SSB,
the 2510 (or Lincoln these days) may be a better
choice for some than the 2950.
> The one thing that you do have to be careful of with a 2510 (and the
> President Jackson, which has virtually the same transmitter) is the
> power control circuit. The power control derives it's feedback from an
> SWR sensing diode, which allows the transmitter to back down the power
> when the SWR gets high, thereby saving the final. But an unpleasent side
> effect of this circuit is that under certain conditions, (such as the
> input matching of a amplifier) the feedback can be greatly reduced which
> results in the rig putting out too much power. This can cause overdrive
> of the amplifier, and the distorted sound you get when you have no
> forward swing and all back swing.
That's interesting. I've never noticed that effect.
My backup radio is a Jackson. I'll have to run it
into some loads other than 50 ohms to see how it
reacts.
You'd figure the opposite of what you say would be
true. On either side of 50 ohms, the control
circuit should reduce the output. There shouldn't
be a condition where the output increases.
> Dave
> "Sandbagger"
Bill Eitner
The difference here is that Ranger offered it
themselves knowing that some hams are interested
in 10 meter FM repeater operation. As I remember,
it's spoken of in the owners manual. In other
words, I wasn't talking about a totally aftermarket
unit. However, since I've never followed it up,
there's nothing saying that Ranger ever produced
a custom PL board for those radios. There certainly
are no empty sockets inside the radio to ease the
installation.
Dave Hall
>
> Those radios have no "over-SWR protection" in them.
>
> The only type of protection that they have is overheat, and that is done
> through a simple thermister.
>
> The problem that you are seeing is because of a higher than what is called
> for input impedance on cheaper or bad amplifiers.
>
> A transmitter will put out 4 watts into a 50 ohm load...
>
> It will not put out 4 watts into a 75 ohm load (way less, as a matter of
> fact, and this is a 2 to 1 swr).
>
> Consequently, when driven into a 40 or 30 ohm load, the SWR goes up, but
> their is more current in the feedline to the box, resulting in greater
> drive!
>
Look at the schematic again! You'll notice a diode that rectifies
reflected RF power, and sends this negative voltage to the AM power
adjustment pot. When more reflected power is present, the negative
feedback increases and the power falls off proportionally. If that isn't
a protection feature, then I don't know what is.
Dave
"Sandbagger"
Dave Hall
>
> Again, I agree. The meter is lousy too.
Very, but I've hooked up an external analog meter, and it works fine.
Hmm.... I've never noticed any problem with positive modulation from a
2510. The radio's amplifier is capable of producing between 40 and 50
watts peak power on SSB (after tuneup), and would produce the same
carrier level, if the carrier were set to full on. With this in mind,
peak AM modulation should also fall in the 40 to 50 watt range, which
should allow 100% modulation of a 10 watt carrier. My testing on my own
2510 seems to bear this out, as I have no problem getting 100% (4X) peak
power with a 10 watt carrier. The modulation envelope is "normal" at
this level. Lower carrier levels of 4 or 5 watts, gives an even more
peak power ratio if the limiter is not set to hold at 100%.
Generally speaking, most radios will lower total peak power, when
carrier is dropped, unless a "swing" type mod is employed to bypass the
AC modulation component (the capacitor) around the resistor that lowers
the carrier level.
>
> On the other hand, the 2510 will show higher peak
> power output with a simple tune-up on SSB than a
> 2950. They have a nice, stable SSB sound too.
> If a guy could handle the lower tech CPU with its
> lack of features, and is only interested in SSB,
> the 2510 (or Lincoln these days) may be a better
> choice for some than the 2950.
The output of a 2950 on SSB is typically in the 35 watt range. The 2510
will easily top that by at least 10 watts (and with a single final).
>
> > The one thing that you do have to be careful of with a 2510 (and the
> > President Jackson, which has virtually the same transmitter) is the
> > power control circuit. The power control derives it's feedback from an
> > SWR sensing diode, which allows the transmitter to back down the power
> > when the SWR gets high, thereby saving the final. But an unpleasent side
> > effect of this circuit is that under certain conditions, (such as the
> > input matching of a amplifier) the feedback can be greatly reduced which
> > results in the rig putting out too much power. This can cause overdrive
> > of the amplifier, and the distorted sound you get when you have no
> > forward swing and all back swing.
>
> That's interesting. I've never noticed that effect.
> My backup radio is a Jackson. I'll have to run it
> into some loads other than 50 ohms to see how it
> reacts.
>
> You'd figure the opposite of what you say would be
> true. On either side of 50 ohms, the control
> circuit should reduce the output. There shouldn't
> be a condition where the output increases.
Yes, Agreed, but what seems to be happening (and I don't have the
equipment to verify this) is that you set the output power into a
"normal" load, which is usually not a flat 1:1 50 ohm load, but rather,
has some small reflective amount, but not enough to be problematic. Then
when you change to the input matching of an amplifier, there is either a
better match, or there are reactive components that "fool" the sense
diode, and result in less feedback being generated and the power of the
radio increases, which results in overdrive. I've wanted to bypass the
feedback circuit so that this isn't a problem, but the power adjust
relies on negative feedback voltage. Removing this causes the carrier to
go full on. I haven't troubled myself enough to design a fixed negative
voltage source to utilize, or to explore redesigning the carrier balance
circuit. Since I haven't used my 2510 with an amplifier lately, further
work in this area, have been back-burnered.
Dave
"Sandbagger"
Dave Hall
>
> Dave Hall wrote:
> >
> > Bill Eitner wrote:
> > >
> > > Dave Hall wrote:
> > >
> > > > The 2950 does PL tones? Since when? I know mine doesn't. All mine has is
> > > > a stupid roger beep. It does do splits quite nicely though.
> > >
> > > Supposedly they will after you add the optional
> > > add-on board. I've never ordered, obtained, or
> > > installed one, so don't ask. All I know is that
> > > it's supposed to be available.
> > >
> >
> > Oh, and add-on extra. That's different. Yea, and you can also add a
> > speech compressor too, as an add-on.
> >
> > Any radio can do PL tones, with the addition of a PL encoder board, such
> > as a Com-Spec unit.
>
> The difference here is that Ranger offered it
> themselves knowing that some hams are interested
> in 10 meter FM repeater operation. As I remember,
> it's spoken of in the owners manual. In other
> words, I wasn't talking about a totally aftermarket
> unit. However, since I've never followed it up,
> there's nothing saying that Ranger ever produced
> a custom PL board for those radios. There certainly
> are no empty sockets inside the radio to ease the
> installation.
>
Nor are there any "functions" on front panel to facilitate operation of
a multi-PL encoder, if one were designed to work with this particular
model.
Dave
"sandbagger"
2-IR-082 Tim
> lack of features, and is only interested in SSB,
> the 2510 (or Lincoln these days) may be a better
> choice for some than the 2950.
hi bill. with all the mods you guys discuss here you would think that you new
about the chipswitch. take a look at the other cpu available for the 2510. ive
ran a few of them and found them to be fantastic performers with tons of more
features than any 2950.
best regards, Tim 2-IR-082 Texas USA
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Philip de Cadenet
Good questions.
>> I was just wondering what class works best with A.M. and SSB . Or if all of
>> them will work but some may sound better than others.
>> Sorry for too such of a broad question.
>> Tinker
Just my thoughts on SSB FWIW. I hope Bill won't disagree:-)
Bill, drop me an e-mail detailing some of this 'leading-edge' research,
I'm genuinely interested.
How I read what works for me being primarily interested in the very best
possible sounding SSB mobile signal.
Class AB bias is adjusted so that Icq equals approximately 0.5-2.5% of
maximum specified collector current. This translates into 100-500mA per
transistor (2879) or 200-1000mA per pair of devices. This mode yields
acceptable linearity for SSB operation and higher efficiency (40-60%)
than class-A. The Toshiba 2SC2879 data sheet specifies a minimum Icq of
100mA per transistor for class-AB operation. I have found that by
increasing Icq to 500mA per transistor results in increased linearity
and lower IMD and harmonics.
People on air have asked how my amp (homebrew 8-pill) sounds so good as
compared to factory ham band amp's, Metron, Henry, SGC, Ten Tec Hercules
etc. The higher Icq is the reason.
You may ask why the factories don't increase Icq. Because it costs more
dollars to build a separate high current bias source for each pair of
transistors and even more to produce an amp that will remain stable with
a high Icq. So the factories use the minimum recommended Icq because it
is cheaper and it yields satisfactory results.
Since I've never been satisfied with satisfactory performance my unit
has independent bias adjustment per pair of devices.
Class-B bias is adjusted so that Icq is just equal to the leakage
current (Iceo). the transistor is just barely cut off and any drive
signal causes the collector current to flow. This mode yields acceptable
linearity for some AM applications and higher efficiency (60-70%) than
class-AB.
The Skywalker amp kits are probably not what you're after as they are
designed for 1.8-30MHz operation and are therefor not really optimised
for 11m.
Phil / UK
>--
>> Bill Eitner wrote in message <37E6C71E...@netzero.net>...
>> >That's too big a subject to properly handle in this forum. I suggest
>> >borrowing a copy of The ARRL Handbook or a copy or The Radio Handbook
>> >from a local library and reading the sections that pertain to that.
>> >After you've done that, if you have any specific questions they can
>> >be fielded here.
>> >--
>> >Tinker wrote:
>> >>
>> >> I was wondering what the classes of amps really mean ? Could anyone give
>> me
>> >> quick rundown ?
>> >> Thanks,
>> >> Tinker
>> >
>> >
Toll Free
Got the tube. Thanks.
The Commander, Pride (Solid State) and Palomar 250 and 300A (Solid State)
all had adjustable bias for each pair of devices.
You could really make one of those amps sing, if you knew what you where
doing. I had many truckers sold on my work just after selling them one of
those amps and tuning it (both the radio to the amp, and the bias to the
drive level) together.
Your right. The higher Iq does make a difference on sideband.
Now, if you would only finish that 3CX3000 mobile! we would be able to hear
you stateside!
hehe
Toll Free
Philip de Cadenet <BigM...@invest.fsbusiness.co.uk> wrote in message
news:r7z08dAP...@invest.fsbusiness.co.uk...
LDD7777
had Tx locked down(with a 59 made 2 pill).He and i talked for a good 15 mins.
Take care 1200........
Bill Eitner
Buying and installing a chipswitch takes the cost of the radio
way above and beyond that of a 2950. In other words, a 2510 clone
with a chipswitch is not a better value than a 2950.
--
Bill Eitner
> > > I find the audio of the 2510 to be just fine. You just have to keep the
> > > carrier level to less than 15 watts, and you'll be ok. On the scope, you
> > > cannot tell the difference between the 2510's low level modulation, and
> > > that of another radio with high level modulation.
> >
> > Here, I disagree. In my experience, you have to
> > lower the carrier to 5 watts before you'll see
> > 100% positive modulation on a scope. The modulation
> > envelope peaks are alot more rounded too. The
> > waveform doesn't look like a textbook AM modulation
> > envelope at all. You can see the effect of the
> > linear stages that the signal has been put through.
> > Comparing tuned-up radios, the diffierence between a
> > 2510 and a 2950 on AM using a scope or a monitor receiver
> > is very clear. The only way to make a 2510 even
> > come close is to reduce the carrier to the point
> > where the maximum peak power begins to drop. That
> > happens in the 4 to 5 watt range. At that point,
> > you've got all the positive modulation you're going
> > to get. The sound isn't too terribly bad, but the
> > high-level AM "bark" just isn't there. I don't
> > like the fact that you lose peak power when you
> > lower the carrier below about 5 watts either.
> > That compromises the performance when using CB
> > amps that show symptoms of overdrive if the carrier
> > is above 2 to 2.5 watts.
>
> Hmm.... I've never noticed any problem with positive modulation from a
> 2510.
Then you've never really compared it to a high-level AM
radio on a scope. The difference is plain as day. It
would be even more plain if you could look at it using
the trapezoidal method. The drawback is you need a decent
audio signal to do it that way. Low level AM doesn't lend
itself to that method.
> The radio's amplifier is capable of producing between 40 and 50
> watts peak power on SSB (after tuneup), and would produce the same
> carrier level, if the carrier were set to full on.
That doesn't mean a thing. It's the ability to fully
modulate the carrier is what we're talking about. There
may be enough audio to fully modulate the carrier way
back at the TX mixer, but when put through a bunch of
linear amp stages the positive modulation percentage
noticeably decreases. Think about it. If that wasn't
the case, why would anybody use the more expensive
high-level technique?
> With this in mind,
> peak AM modulation should also fall in the 40 to 50 watt range, which
> should allow 100% modulation of a 10 watt carrier.
That's absolutely untrue. There's no connection between
SSB peak and AM peak in a low-level AM radio. For example,
my Jackson peaks lower on AM than my 2950, but it peaks
higher than my 2950 on SSB.
> My testing on my own
> 2510 seems to bear this out, as I have no problem getting 100% (4X) peak
> power with a 10 watt carrier.
Then you should check your test set-up. You may be seeing
what you expect rather than what is really there. Remember
to limit your test to 100% NEGATIVE modulation. In other
words, set the carrier level, then inject a steady 1kHz
tone and ramp it up just to the point of 100% NEGATIVE
modulation. (I'm assuming you know how to do that.) At that
point, measure the percentage of POSITIVE modulation. If the
carrier is higher than 4 or 5 watts, the positive modulation
will be below 100% even though the negative modulation is at
100%. That's the problem with low-level AM radios. It gets
worse as you ramp up the carrier (dead-key) power.
> The modulation envelope is "normal" at
> this level.
No it's not. You're fooling yourself.
> Lower carrier levels of 4 or 5 watts, gives an even more
> peak power ratio if the limiter is not set to hold at 100%.
We're not talking about unlimited modulation. We're talking
about ratios within the 100% boundary. Another easy
check is to verify average power. Given what you've
said, the 2510 should be able to hold an average wattage
of just under 15. That couldn't be more false. Set the
dead key wattage to 15 and then modulate the carrier
while monitoring the average power using a Bird. The
power reading will decrease with modulation no matter what.
That indicates an average power that is less than the dead-key
power.
> Generally speaking, most radios will lower total peak power, when
> carrier is dropped, unless a "swing" type mod is employed to bypass the
> AC modulation component (the capacitor) around the resistor that lowers
> the carrier level.
That all sounds nice, but let's stay on track here.
In every AM performance parameter we can think of, the
2950 will easily outperform the 2510. That's what this
is all about.
> >
> > On the other hand, the 2510 will show higher peak
> > power output with a simple tune-up on SSB than a
> > 2950. They have a nice, stable SSB sound too.
> > If a guy could handle the lower tech CPU with its
> > lack of features, and is only interested in SSB,
> > the 2510 (or Lincoln these days) may be a better
> > choice for some than the 2950.
>
> The output of a 2950 on SSB is typically in the 35 watt range. The 2510
> will easily top that by at least 10 watts (and with a single final).
It's not by "at least 10 watts." It's more like 5. On the
other hand, the 2950 beats the 2510 on AM by 5 peak watts and
more when maximum peak to carrier ratio is considered. Don't
get carried away.
First, Toll Free doesn't agree. I tend to believe Toll over you.
I've stared at 2510 schematics for hours trying to figure out bizarre
problems. I've never noticed the circuit you speak of either.
You're going to have to lay out some part numbers and circuit
analysis to convince me.
>
> Dave
> "Sandbagger"
Bill Eitner
>
> Tinker,
>
> Good questions.
> >> I was just wondering what class works best with A.M. and SSB . Or if all of
> >> them will work but some may sound better than others.
> >> Sorry for too such of a broad question.
> >> Tinker
> Just my thoughts on SSB FWIW. I hope Bill won't disagree:-)
I do disagree with much of what you've written.
See below for details.
> Bill, drop me an e-mail detailing some of this 'leading-edge' research,
> I'm genuinely interested.
Forget the e-mail. I'm going to roast you here just like
you tried to roast me. Grab as much of the leading edge
stuff as you can.
> How I read what works for me being primarily interested in the very best
> possible sounding SSB mobile signal.
Forget what you've read. Test the leading edge research
rather than passing it off so quickly.
> Class AB bias is adjusted so that Icq equals approximately 0.5-2.5% of
> maximum specified collector current. This translates into 100-500mA per
> transistor (2879) or 200-1000mA per pair of devices. This mode yields
> acceptable linearity for SSB operation and higher efficiency (40-60%)
> than class-A. The Toshiba 2SC2879 data sheet specifies a minimum Icq of
> 100mA per transistor for class-AB operation. I have found that by
> increasing Icq to 500mA per transistor results in increased linearity
> and lower IMD and harmonics.
The trick is to forget test equipment based specs and go
by what your monitor (you have a monitor don't you) says.
> People on air have asked how my amp (homebrew 8-pill) sounds so good as
> compared to factory ham band amp's, Metron, Henry, SGC, Ten Tec Hercules
> etc. The higher Icq is the reason.
That's all useless anecdotal evidence. If you're going to
roast me, I'm going to call you a liar to your face. You
couldn't be more wrong by acknowledging quiescent collector
current as the reason why your system gets good reports.
> You may ask why the factories don't increase Icq. Because it costs more
> dollars to build a separate high current bias source for each pair of
> transistors and even more to produce an amp that will remain stable with
> a high Icq. So the factories use the minimum recommended Icq because it
> is cheaper and it yields satisfactory results.
It's more than that. The amps actually work better with
less bias. Class B lives even though you don't recognize
it, believe in it, or understand it.
> Since I've never been satisfied with satisfactory performance my unit
> has independent bias adjustment per pair of devices.
What the fuck does that mean? Re-read that with the
understanding that you didn't write it. I hate to say
it, but you lost it right here. Nobody cares about your
amp when you're debating me. We're dealing with concepts
here, not how your personal amp responds.
> Class-B bias is adjusted so that Icq is just equal to the leakage
> current (Iceo). the transistor is just barely cut off and any drive
> signal causes the collector current to flow. This mode yields acceptable
> linearity for some AM applications and higher efficiency (60-70%) than
> class-AB.
This type of operation IS the leading edge. Class B has
all the benefits and no disadvantages. Forget your biases
and go with it.
> The Skywalker amp kits are probably not what you're after as they are
> designed for 1.8-30MHz operation and are therefor not really optimised
> for 11m.
27 MHz is in the 1.8 to 30 MHz range--isn't it?
You're not an idiot. Bias your amp just to the point where
there's no audible distortion on SSB. THAT is Class B bias
and one leading edge facet of amplifier development. Store
this one comment as a research based golden nugget.
> Phil / UK
Philip de Cadenet
>Got the tube. Thanks.
Great, that'll teach me never to use our Royal Mail again.
>The Commander, Pride (Solid State) and Palomar 250 and 300A (Solid State)
>all had adjustable bias for each pair of devices.
but most all of these models go back to the 70's & 80's? Prior to
legalisation of CB here in the UK in 81 very few people imported stuff
from the US. It was mostly Euro junk as now.
I personally brought in Varmints and some Grays. On my travels around
the US back then including visiting a few CB jamborees. I had problems
tracking down sources of amp's. I managed to track down Messenger in WA,
Hurricane, Storm & Tornado in NY and if my memory serves me right Texas
Stars in NC. Other than the Messengers I never was sure if I'd found the
actual source.
Anyhow I'm into other kinds of amp's these days. Kind of gone up a step
or two if you know what I mean.
>You could really make one of those amps sing, if you knew what you where
>doing. I had many truckers sold on my work just after selling them one of
>those amps and tuning it (both the radio to the amp, and the bias to the
>drive level) together.
>
>
>Your right. The higher Iq does make a difference on sideband.
>
>Now, if you would only finish that 3CX3000 mobile! we would be able to hear
>you stateside!
I've left the 3CX3000A7 with my friend John. It's in a Henry plasma
generator rack c/w 3-phase PSU.
My mobile will have to wait. Some auto dealer in MO has screwed me on my
Suburban which I'll probably now never see! That'll teach me to trust
auto dealers.
I'll consider buying another when I've put some more money by.
My present mobile is limited by space for extra alternators. A single
200A is all that's possible and this has therefor limited me to running
my 8-pill.
Remember, I also have the 3CX2500 which I may put together but a
suitable vehicle really must come first. I have no experience with
generating AC power in a mobile though I consider I have DC power
generation down to a fine art. I go about it differently than most all
you guys and have no problem holding voltage on key down.
Phil / UK
Philip de Cadenet
I'm not trying to roast anyone.
> Forget the e-mail. I'm going to roast you here just like
> you tried to roast me. Grab as much of the leading edge
> stuff as you can.
Will do.
> That's all useless anecdotal evidence. If you're going to
> roast me, I'm going to call you a liar to your face. You
> couldn't be more wrong by acknowledging quiescent collector
> current as the reason why your system gets good reports.
Well there is a noticeable difference between A & B when you listen to
it on air.
>
>> You may ask why the factories don't increase Icq. Because it costs more
>> dollars to build a separate high current bias source for each pair of
>> transistors and even more to produce an amp that will remain stable with
>> a high Icq. So the factories use the minimum recommended Icq because it
>> is cheaper and it yields satisfactory results.
>
> It's more than that. The amps actually work better with
> less bias. Class B lives even though you don't recognize
> it, believe in it, or understand it.
I will open my unit up and look at it on the analyser. Last did that
nearly two years ago.
>
>> Class-B bias is adjusted so that Icq is just equal to the leakage
>> current (Iceo). the transistor is just barely cut off and any drive
>> signal causes the collector current to flow. This mode yields acceptable
>> linearity for some AM applications and higher efficiency (60-70%) than
>> class-AB.
>
> This type of operation IS the leading edge. Class B has
> all the benefits and no disadvantages. Forget your biases
> and go with it.
OK, I hear where you're coming from.
>
>> The Skywalker amp kits are probably not what you're after as they are
>> designed for 1.8-30MHz operation and are therefor not really optimised
>> for 11m.
>
> 27 MHz is in the 1.8 to 30 MHz range--isn't it?
Well yes, but, in Lee's Skywalker output transformer design he mentions
using type 43 material as against the maybe more popular type 61. The 61
material has a lower initial permeability (125), higher resistively
(10p8), and higher curie temp (350c) compared to type 43 material which
has values of 850, 10p5 and 130c respectively. The type 61 has a higher
resistively than the type 43 which leads to higher efficiency especially
on the higher freq's. He says he decided to go with the 43 due to the
lower initial permeability of the type 61 material yielding a 1" long
transformer with an Xl of only 11 at 1.8MHz which does not meet the
requirement. A 1.5" long type 61 transformer has a Xl of 17 which does
meet the requirement but the longer transformer has a much higher
leakage L which hurts performance on the higher freq's. He decided, just
as Helge did years ago that the best performing design over 1.8-30MHz
results when the type 43 is used in a 1" long package.
He is waiting for someone to design a new ferrite material with high
permeability and high resistively but is not holding his breath as
materials have not changed much in years.
> You're not an idiot.
Yes, this is what my favourite school teacher used to tell me.
> Bias your amp just to the point where
> there's no audible distortion on SSB. THAT is Class B bias
> and one leading edge facet of amplifier development. Store
> this one comment as a research based golden nugget.
I will go and play in the next week or two.
Thank you.
Phil / UK
Toll Free
> Great, that'll teach me never to use our Royal Mail again.
God, don't use UPS. I just had a 16 pill amp destroyed by them, and even
though I insured it, and MADE the company I shipped it from package it, they
denied the claim. Even so, the tube arrived with a nice smash in the box.
I liked the English newspaper, though! Think I will go abroad to buy one of
the cars!!!
> >The Commander, Pride (Solid State) and Palomar 250 and 300A (Solid State)
> >all had adjustable bias for each pair of devices.
> Very few of these ever made it to our shores. Correct me if I'm wrong
> but most all of these models go back to the 70's & 80's? Prior to
> legalisation of CB here in the UK in 81 very few people imported stuff
> from the US. It was mostly Euro junk as now.
Actually not. Most of those (well, the Commander line was older, but mid
80s, I would say) where in the 90s... Palomar (not the originals) and the
others where a decent amplifier, but people killed them with overdrive and
brought the bias up as high as it would go to get more gain... Mo gain = Mo
Watts!
>
> I personally brought in Varmints and some Grays. On my travels around
> the US back then including visiting a few CB jamborees. I had problems
> tracking down sources of amp's. I managed to track down Messenger in WA,
> Hurricane, Storm & Tornado in NY and if my memory serves me right Texas
> Stars in NC. Other than the Messengers I never was sure if I'd found the
> actual source.
You didn't have Texas Star's plant, that's for sure.
Messenger back in those days was a good brand....
Even better if you could have gotten the San Diego built Messengers. A
blind guy built the smaller ones!
>
> Anyhow I'm into other kinds of amp's these days. Kind of gone up a step
> or two if you know what I mean.
Sure do!
> >You could really make one of those amps sing, if you knew what you where
> >doing. I had many truckers sold on my work just after selling them one
of
> >those amps and tuning it (both the radio to the amp, and the bias to the
> >drive level) together.
> >
> >
> >Your right. The higher Iq does make a difference on sideband.
> >
> >Now, if you would only finish that 3CX3000 mobile! we would be able to
hear
> >you stateside!
> I've left the 3CX3000A7 with my friend John. It's in a Henry plasma
> generator rack c/w 3-phase PSU.
Good choice. Those are good for 8 to 10 grand with a roller inductor and
two Jennings in them.
>
> My mobile will have to wait. Some auto dealer in MO has screwed me on my
> Suburban which I'll probably now never see! That'll teach me to trust
> auto dealers.
Bummer.
When you are ready again, let me know. My sister-in-law still works at an
auto auction.
>
> I'll consider buying another when I've put some more money by.
>
> My present mobile is limited by space for extra alternators. A single
> 200A is all that's possible and this has therefor limited me to running
> my 8-pill.
Oh well.
Look to Mitsubishi alternators. They have a 500A DC output alternator that
goes in the Ford Powerstroke Emergency Vehicles. I have seen one, and it
will do every bit of 500A DC.
About the same size as the 300A Leece Neville's.....
>
> Remember, I also have the 3CX2500 which I may put together but a
> suitable vehicle really must come first. I have no experience with
> generating AC power in a mobile though I consider I have DC power
> generation down to a fine art. I go about it differently than most all
> you guys and have no problem holding voltage on key down.
You ever sell the 2500, I get first dibs!
Gotta run.
Toll Free
2-IR-082 Tim
>Buying and installing a chipswitch takes the cost of the radio
>way above and beyond that of a 2950. In other words, a 2510 clone
>with a chipswitch is not a better value than a 2950.
dont think your stupid at all, just purposely not mentioning it since you dont
like the 2510. it may not be a better value but it makes it a much better radio
than the 2950 or any other type in the class.
Bill Eitner
doesn't make the radio better than a 2950. Quantity doesn't
outweigh quality. The Chipswitch adds many documented features
that don't amount to anything. Where are the PLL tones? Where
is the high-level AM modulation? The Chipswitch doesn't add the
features that would REALLY make a 2510 equal to or better than
a 2950. The Chipswitch features are mostly fluff. The best
thing about the Chipswitch is that it'll convert a 2600 for CB
operation. I bet more of them are sold for that reason alone than
anything else.
--
2-IR-082 Tim
>I disagree. I've installed Chipswitches. The resulting change
>doesn't make the radio better than a 2950. Quantity doesn't
>outweigh quality. The Chipswitch adds many documented features
>that don't amount to anything. Where are the PLL tones? Where
>is the high-level AM modulation? The Chipswitch doesn't add the
>features that would REALLY make a 2510 equal to or better than
>a 2950. The Chipswitch features are mostly fluff. The best
>thing about the Chipswitch is that it'll convert a 2600 for CB
>operation. I bet more of them are sold for that reason alone than
>anything else.
what radio are you comparing it to that has pll tones? i thought we were
talking about ten meters only rigs. the only one i know about with the pll
tones is the 2600. i use my 2510 on ssb only and never use AM so thats not a
concern. here where i live were all near three major freeways and the folks
with 2950's dont hear anything when the truckers with class c boxes come thru
ripping stuff up. same situation when the dx is high and all the signals from
27.025 are 30 over 9. the radios with loose recives like the 2950 and other
exports just dont cut it. if i was living in the boon docks by myself with no
dx then a 2950 would suit me fine but thats not a real world scenario.
Philip de Cadenet
>Look to Mitsubishi alternators. They have a 500A DC output alternator that
>goes in the Ford Powerstroke Emergency Vehicles. I have seen one, and it
>will do every bit of 500A DC.
Nearest I could get to Mitsubishi alternators was their N. american
automotive Electrical parts site.
No listing of individual alternators. That rascal just has to be a
special. Any chance of finding the part or model number? I'd very much
like to chase it up.
I will however fax them later today.
>About the same size as the 300A Leece Neville's.....
>
>>
>> Remember, I also have the 3CX2500 which I may put together but a
>> suitable vehicle really must come first. I have no experience with
>> generating AC power in a mobile though I consider I have DC power
>> generation down to a fine art. I go about it differently than most all
>> you guys and have no problem holding voltage on key down.
>
>You ever sell the 2500, I get first dibs!
I will get data sheets first on both tubes and decide which one to keep.
I'll bring the other one over and use it as a deposit on a Sub!
Tnx
Phil / UK
Bill Eitner
>
> >
> >I disagree. I've installed Chipswitches. The resulting change
> >doesn't make the radio better than a 2950. Quantity doesn't
> >outweigh quality. The Chipswitch adds many documented features
> >that don't amount to anything. Where are the PLL tones? Where
> >is the high-level AM modulation? The Chipswitch doesn't add the
> >features that would REALLY make a 2510 equal to or better than
> >a 2950. The Chipswitch features are mostly fluff. The best
> >thing about the Chipswitch is that it'll convert a 2600 for CB
> >operation. I bet more of them are sold for that reason alone than
> >anything else.
>
> what radio are you comparing it to that has pll tones?
None of them do, but that would be a feature that would
actually make the 2510 better than a 2950.
> i thought we were
> talking about ten meters only rigs.
We are.
> the only one i know about with the pll
> tones is the 2600.
2600s don't have PLL tones stock.
> i use my 2510 on ssb only and never use AM so thats not a
> concern.
Then you should know for a fact that as CBers are
concerned there's nothing that the Chipswitch does
that really makes the radio stand out in the group.
> here where i live were all near three major freeways and the folks
> with 2950's dont hear anything when the truckers with class c boxes come thru
> ripping stuff up.
That's crap. The 2950 receiver isn't as selective
as the 2510, but it's not like you're going to hear
people on the 2510 that you're not going to hear on
the 2950. I've performed experiments that prove it.
I've compared the 2950 to all the radios that are
supposed to have "hot" receivers. None are more
sensitive, most are more selective--but that's it.
> same situation when the dx is high and all the signals from
> 27.025 are 30 over 9. the radios with loose recives like the 2950 and other
> exports just dont cut it. if i was living in the boon docks by myself with no
> dx then a 2950 would suit me fine but thats not a real world scenario.
That's just more crap. When the skip is in like
that it doesn't matter what radio you're using--
the receiver will be burried in it.
I've used 2950s for 10 years. They aren't the
most selective receiver, and there are several
receiver stages where they should have used FETs
rather than bipolars so the no-signal noise floor
is higher than it should be, but they aren't THAT
bad. There are a few cheap mods that improve the
receive performance by about 10%. Having someone
who's patient and has good signal to noise ratio
measurement equipment align it helps quite a bit
too. Like I said, I've done tests that prove it.
Some of the seemingly very quiet receivers won't
hear fringe signals as well as a properly modified
and aligned 2950. What some see as superior
selectivity is just a lack of sensitivity.
In any case, we're both getting off the point.
The Chipswitch certainly is not the reason why
the 2510 types are more selective than the 2950.
It's a wash. The receiver selectivity is countered
by its lousy AM transmit performance. At best,
the 2510s AM transmitter is the equal of the 2950s
receiver. In other words, with the proper mods
and tuning, the 2510 AM transmitter is okay just
like the 2950 receiver. The Chipswitch doesn't
improve the 2510s AM transmit performance. It
doesn't give the 2510 PLL capability either. It
gives the 2510 some memory locations and the
ability to scan and search. Those are the useful
features, but the 2950 already has those features.
The rest is basically useless fluff.
The bottom line is that a 2510 with a Chipswitch
is not a better value than the 2950, therefore
it's not a better choice.
Remember, I did admit that if SSB is all you do,
than a stock 2510 (Lincoln) may be the better
choice. Personally, I stick with the 2950, but
alot of people I know, mostly hams, prefer the
2510 types. That's why there's chocolate and
vanilla. A radio choice always has to be based
on what the person is primarily using the radio
for. There is no one "best for everything" radio.
There are always people asking that, and I'll
try to answer it, but there will always be areas
of the radios I recommend that can be nit-picked.
The same goes for anyone else's choices.
--
>
> best regards, Tim 2-IR-082 Texas USA
>
> IRDX GROUP OFFICIAL SITE:
> HTTP://HOME.WXS.NL/~19IR01
>
> 11 Meter Dx News **Updated Daily**
> http://home.t-online.de/home/IRDX.GERMANY/dxnews~1.htm
>
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2-IR-082 Tim
hi bill,
i'm not sure how you got to talking about what you did. i wasnt saying that the
2510 had a more sensitive recieve only a more selective one. here in a area
around a lot of channel 6 operators and 3 freeways thats the most important
thing. bill you can test and talk about them anything you want. are we supposed
to just take your word on every little thing, perhaps you only report what
suits you. to me you sound like a 2950 dealer protecting business. i myself
frequently enjoy the dual watch feature of the chipswitch as well as the
ability to go from 12 to 10 meters in the same radio. with a few mods to the
recieve of the 2510 and youll have a even better radio than the 2950 modded or
not. all anybody has to do is open both radios up and look at them side by
side. i would say that the difference in the heat sinks alone is a good
indicator of which radio is higher quality not to mention the more heavy duty
circuit boards and every other detail. if a person is a free band operator
working from the mobile a chipswitched 2510 is the way to go. the seperate
programable tunning steps make this radio a breeze to work while driving. i
have mine set for a 5kc jump up or down when the button is pushed. what bill
calls extra fluff are all features i use everyday. true enough if your just a
AM'er that stays on one channel all day you may not need the 2510 but if your a
serious side band dx'er theres no better radio in the class. the people i talk
to dont even use am so bills argument isnt good for what we do.
CHIPSWITCH Enhanced Microcomputer.
The HR2510 / HR 2600 / LINCOLN 10 METER Amateur Radios manufactured by the
UNIDEN Corporation of America do not encompass many of the useful and desirable
features of the modern day Amateur radio. The Chipswitch IC is a custom
microcomputer chip (integrated circuit) which is programmed to give new life
and value to your UNIDEN radio.
30 MEMORY CHANNELS WITH TEMPORARY CHANNEL LOCKOUT AND REPEATER OFFSETS
The original HR2510 / HR2600 / LINCOLN has basically one memory available to it
in the sense that it remembers the frequency you were last on during a power
interruption. The CHIPSWITCH supplies you with three groups of MEMORY BANDS.
There are now ten (10) user programmable frequency channels available for each
MEMORY BAND. You can elect to have repeater offsets to any of the stored memory
channels. You are also provided with the ability to lockout any memory
channel(s) temporarily during SCAN/SEEK functions.
EXTENDED FREQUENCY COVERAGE
Adding the CHIPSWITCH IC will allow the radio to operate contiguously from 11
through 10 meters without any further modifications. Installation
instructions are available for review.
With additional modifications to the PLL PCB, the CHIPSWITCH allows full
contiguous coverage from 24.800 to 29.999 MHz. (12 through 10 Meters).
Modifying these radios for use in the 12 Meter range can be done at a few
sites. Although with the Chipswitch, these radios could be operable to 15
Meters, some spurs near 15 Meters cannot be adjusted out, therefore a password
has been added to the Chipswitch program to disallow access beyond 12 Meters at
this time.
PROGRAMMABLE SCAN/SEEK FUNCTION
The original HR2510/HR2600/LINCOLN allows you to scan on an arbitrary 'band
basis." This new feature allows you to select a range of frequencies for SCAN
and SEEK while in band 0, or SCAN/SEEK by memory channels in band 1, 2 and 3.
The SCAN feature allows you to set the 'hold-time' (the amount of time the
radio waits to resume its scan function after that particular frequency quiets
down). The SEEK feature is identical to the SCAN except for when the radio is
scanning and detects activity on a frequency, the radio will receive on that
particular frequency for a user-programmed length of time before it continues
the scan. SCAN and SEEK are completely user programmable for 5 or 10 kHz steps
in band 0.
PROGRAMMABLE CHANNEL UP/DN BUTTONS
This provides you with the ability to program the radio's channel up and
channel down buttons to change channels/frequencies in any of five (5)
different ways. (5 kHz, 10 kHz, Underlined digit, etc.
PROGRAMMABLE MICROPHONE CHANNEL UP/DN BUTTONS
This provides you with the ability to program the microphone channel up and
down buttons to change channels/frequencies in any on of eight (8) different
ways.
SPLIT FREQUENCY OPERATION
When enabled, this allows you to transmit on one frequency, and receive on
another.
PROGRAMMABLE TRANSMITTER TIMEOUT
This feature provides the radio with a built-in QSO timer. When enabled, it
triggers a programmable timer the moment the radio starts transmitting. When
the user-programmed length has been achieved, the radio will stop transmitting.
To continue transmitting, just release and press the microphone PTT (Push To
Talk) Button.
PROGRAMMABLE TRANSMIT FREQUENCY RANGE
This provides you with the ability to program a range of frequencies to
operationally transmit on. In this mode of operation, you still have the
ability to receive frequencies out of the user-programmed range, but can not
transmit on them.
PRIORITY CHANNEL (Requires optional hardware)
Priority channel operations allow you to program any frequency (i.e. home
frequency, etc.) and have the HR2510/HR2600/LINCOLN check this frequency while
you are on another, at a user-programmed rate. This feature will not function
properly without the optional PRIORITY CHANNEL BOARD.
MISCELLANEOUS
The 'SPAN UNDERLINE CURSOR' now has a 'phantom' 4th position (all 3 underline
bars) cursor. This enables you to go through the band in 100 kHz increments.
This 'phantom' 4th position is indicated by 3 cursors.
The 'SPAN UNDERLINE CURSOR' position and the underlined digit can be moved by
pressing both microphone buttons at the same time. (Great for mobile operation)
The button repeat rate is now programmable.
The internal 'button beep' duration is now programmable from 0 to 0.5 seconds.
The 'RPTR' button on the HR2600, when depressed, will transmit the CTCSS tone
to open up a repeater station. Repeater offset selection is required when
programming memory frequencies.
The HR2510/HR2600/LINCOLN now has two function modes:
OPERATE MODE
This mode is the radio's normal operation mode.
PROGRAM MODE
The front panel controls are used to program information the radio will use
during OPERATE MODE (i.e. memory channel frequencies, split channel, scan
functions, etc.)
INSTALLATION
As the name CHIPSWITCH implies, the basic modification of the radio is the
replacement of the existing UNIDEN microcomputer chip. A person proficient in
soldering/desoldering techniques on P.C. boards is qualified. A comprehensive
installation manual is provided. No modification to the front panel is required
as all the new features are controlled by the existing knob and buttons on the
front panel. The optional PRIORITY CHANNEL BOARD and 12 METER MODIFICATION KITS
do require modifications to the circuit boards.
Brass
<p...@invest.fsbusiness.co.uk> wrote:
> Toll,
>
> >Look to Mitsubishi alternators. They have a 500A DC output alternator that
> >goes in the Ford Powerstroke Emergency Vehicles. I have seen one, and it
> >will do every bit of 500A DC.
> Nearest I could get to Mitsubishi alternators was their N. american
> automotive Electrical parts site.
>
> No listing of individual alternators. That rascal just has to be a
> special. Any chance of finding the part or model number? I'd very much
> like to chase it up.
>
Get in line . . . I was there first . . .LOL
Brass
Philip de Cadenet
>> >Look to Mitsubishi alternators. They have a 500A DC output alternator that
>> >goes in the Ford Powerstroke Emergency Vehicles. I have seen one, and it
>> >will do every bit of 500A DC.
>> Nearest I could get to Mitsubishi alternators was their N. american
>> automotive Electrical parts site.
>>
>> No listing of individual alternators. That rascal just has to be a
>> special. Any chance of finding the part or model number? I'd very much
>> like to chase it up.
>>
>
>
>
>Brass
Phil / UK