14 volt battery/options ?
Phil Stade
It has been suggested that my problems with a Radair 10S may be due in
part to lack of voltage. I use a 12 volt 7.0 amp battery. Is there a
reasonable solution to getting the voltage up to 14? Can two 12 volt
batteries be connected and the resulting 24 volts reduced
electonically to 14 volts? Would a solar panel continuously charging
the 12 volt battery be sufficient to maintain a high enough voltage?
Thanks
Phil Stade
GPSS Canada, (spring is coming soon... isn't it?)
Eric June
Phil,
You can purchase a 2V or even a 4V lead acid battery and wire it in
series with your 12V battery to give you 14V or 16V. Going all the way
up to 24V may cause problems if your equipment is not designed with
voltage regulators that will handle that. If 24V is what you end up
with, check the manuals for your equipment and be sure they can handle
24V input.
You can get 2V and 4V batteries from a variety of sources. The Wings &
Wheels catalog has them: (716) 664-6894. Try and select a 2V or 4V
battery with at least the same ampere-hour rating as your current
battery (i.e. 7 aH min if that is what you have now).
--
Regards,
Eric June
er...@kudonet.com
Hang Gliding Page: http://www.kudonet.com/~ericj/hang.htm
Peter D. Brown
Phil:
Perhaps someone more technically inclined can answer but I will give you
my (limited) understanding.
Most aircraft radios are built to use 13.75 to 14 V because that is the
charging voltage produced for and required by 12 volt battery systems. As
it turns out, the power output of radios falls off pretty dramatically
as voltage falls off so it you take a radio designed for 14V and run it
on a 12 volt battery that is a bit discharged, you are really starting
behind the power curve and its signal strength will drop off pretty
quickly.
Having said that, we operate TX720s on 12 volt batteries and usually get
through a full day without problems. If your battery has a damaged cell
however, it might be low even right after coming off the charger so you
will be starting with significantly less than 12 volts to begin with.
This might explain your problem. Check you battery. I have no idea how
sensitive an older radio such as the Radair 10s is to this problem.
You can either buy or make a 14V pack. The usual assortment of soaring
supply places like Knauff, Wings & Wheels, Pic, etc. can probably sell
you 14 volt batteries and chargers. Alternatively, a trip to the local
electronics store can probably produce a choice of rechargeable batteries
that you can pack in series to get 14V i.e., 1 @ 6 volts and 2@ 4 volts.
SOARING Magazine had an article years ago on how to build an inexpensive
charger for either 12 or 14 volts. If you need a copy I can probably
find it for you.
--
Pete Brown, ASEL/CFIG C-170B
Anchorage, Alaska SGS-1-23G
907-345-7529 (home) 907-564-0223 (fax) Frank Zaic Thermic 18
Richard Kellerman
I would start by reading the manual for the "Radair 10S" to see what its
voltage requirments are. If there is a problem then you can (and
should) purchase individual cells of the appropriate capacity, and
connect them in series. You should also be sure that whatever charger
you use is able to charge a nominal 14V battery. A reasonable rule of
thumb is to charge at 1/20 of the "C" rate - about 400 mA for a 7 A.h
cell.
You should be cautious about just add two cells to an existing 12V
battery, even if the nominal capacity is the same - construction and
even detailed chemical differences might result in less than optimum
performance.
If you hook up a solar panel, forget it, and the sun shines, you will
probably damage the battery unless you go to the trouble of including a
regulator.
If you call Eagle Pitcher, or any other reputable manufacturer of sealed
lead acid batteries, you will get good advice both on batteries and on
chargers.
Richard Kellerman.
Nathan Lemmon
The Radair series of radios was designed in the 60's. Back then,
an audio transistor that behaved properly at any voltage under 12
volts was not commercially available. The cheapest solution to your
problem is to add a 2 volt cell to your battery pack............NL
Jeffry Stetson
In article <34e036b1....@news.calgary.telusplanet.net>, pst...@agt.net
says...
>
>It has been suggested that my problems with a Radair 10S may be due in
>part to lack of voltage. I use a 12 volt 7.0 amp battery. Is there a
>reasonable solution to getting the voltage up to 14? Can two 12 volt
>batteries be connected and the resulting 24 volts reduced
>electonically to 14 volts? Would a solar panel continuously charging
>the 12 volt battery be sufficient to maintain a high enough voltage?
>
>Thanks
>
>Phil Stade
>GPSS Canada, (spring is coming soon... isn't it?)
I can't speak for the Canadian equivalent, but the Radair 10 is on the
the US FCC list of forbidden radios due to off-frequency leakage. The
best solution is a new (cheap) radio. I'm pleased with my $300 panel-
mounted Delcom. The few guys I know still with 12v+2v systems seem to
spend as much time messing with batteries as flying.
Just my opinion, mind you...
--
Jeffry Stetson ... now: Mooney M20E Super 21, Salto H-101
then: Mooney M20C Mark 21, Citabria 7ECA
Grahame Underwood
We have upgraded our 12v gel cell to 14v to run an attitude indicator more
effectively. We got a 2v cell of equivalent a/h rating from a model shop and
strapped it on top. All very successful, but you do need to modify the
charger too !
Regards
Jean Richard
Jeffry Stetson wrote:
> I can't speak for the Canadian equivalent, but the Radair 10 > is on the the US FCC list of forbidden radios due to
> off-frequency leakage.
I don't think it is forbidden here, but if it is in USA, it
won't be long before Canada will do the same. Radio waves
don't have political frontiers (in fact, I should say "not
always have") and countries have some kind of agreements to
manage the radio spectrum the same way.
So, it's not a good idea to invest on a Radair 10 or 10S.
> The best solution is a new (cheap) radio. I'm pleased
> with my $300 panel-mounted Delcom. The few guys I know
> still with 12v+2v systems seem to
> spend as much time messing with batteries as flying.
They are cheap, they work fine, they are probably more
reliable as the four times more expansive Terra, but they
are not always the best solution.
Problems with the Delcom panel mounted :
- if you have to change frequency in flight, with the radio
at the tips of your fingers (or with a finger extension
if you are flying a Jantar unergonomic cockpit), you will
hate those very small wheels that you will have to
manipulate ;
- there's no loudspeaker/microphone jacks on the back ;
you will have to use the front ones and they are
cheap mini jacks like those found on a Walkman ;
- forget using the internal loudspeaker since you won't
hear well enough ;
- forget too about the accessory available loudspeaker/
microphone set ; as a loudspeaker, it's very weak and
as a microphone, the cable will late or soon break
because it is too small ;
- external antenna will also have to be plug beside the
microphone and loudspeaker ; hard to do a nice and clean
mounting.
You get what you are paying for. If you don't have too much
money to invest on a radio and don't mind about the "look"
of your instrument panel, Delcom will do the job (and it's
better to invest in a Delcom than in a Radair).
J. Richard
Jeffry Stetson
In article <34E22F...@sympatico.ca>, j.ri...@sympatico.ca says...
>
>They are cheap, they work fine, they are probably more
>reliable as the four times more expansive Terra, but they
>are not always the best solution.
Oops, you're right. I can't speak for everyone's situation.
>
>Problems with the Delcom panel mounted :
>
>- if you have to change frequency in flight, with the radio
> at the tips of your fingers (or with a finger extension
> if you are flying a Jantar unergonomic cockpit), you will
> hate those very small wheels that you will have to
> manipulate ;
>
True, but the advantage of the thumbwheels is very low power
draw at a very low price.
>- there's no loudspeaker/microphone jacks on the back ;
> you will have to use the front ones and they are
> cheap mini jacks like those found on a Walkman ;
True, but I've never had any problem with them. Also, it
means you can buy accessories like headsets, from Radio
Shack, also saving $$.
>
>- forget using the internal loudspeaker since you won't
> hear well enough ;
True.
>
>- forget too about the accessory available loudspeaker/
> microphone set ; as a loudspeaker, it's very weak and
> as a microphone, the cable will late or soon break
> because it is too small ;
I've never had any problem with mine in the three years I've
used it. I clip the speaker/mike to my shoulder harness and
can hear it fine with the volume turned up maybe half way.
I've been told that some early models were shipped with the
audio gain set (internally) too low, so perhaps this was true
at some earlier time.
>
>- external antenna will also have to be plug beside the
> microphone and loudspeaker ; hard to do a nice and clean
> mounting.
Sort-of true, yet even that has advantages in some installations.
My panel slides into position and has no access from the back.
I've arranged it so the power plugs into one connector on the
bottom and feeds everything. The RG-59 cable is fed through a
small hole a couple inches from the radio front panel and bends
180 degrees to plug into the face. To remove my entire panel, all
I have to do is unplug the antenna & power cables, and unscrew
one thrumb screw. In my case, having the antenna connection
on the front is a plus.
>
>You get what you are paying for. If you don't have too much
>money to invest on a radio and don't mind about the "look"
>of your instrument panel, Delcom will do the job (and it's
>better to invest in a Delcom than in a Radair).
It looks better than the RST that was duct-taped to the
panel before! As far as getting what you pay for, I'm not
so sure. The $2,000+ German radios are ergonomically nice,
but many of my friends with them have had to send them back
for expensive repairs, usually more than once. Each of their
repairs cost more than an entire new Delcom.
Jean Richard
Jeffry Stetson wrote:
> >- there's no loudspeaker/microphone jacks on the back ;
> > you will have to use the front ones and they are
> > cheap mini jacks like those found on a Walkman ;
>
> True, but I've never had any problem with them. Also, it
> means you can buy accessories like headsets, from Radio
> Shack, also saving $$.
Saving at Radio Shack ? Not really. It's better to go to
an electronic parts store and get higher quality. Mini
jacks and plugs are not of the best design, but buying
the best of them is still cheap.
> >- forget too about the accessory available loudspeaker/
> > microphone set ; as a loudspeaker, it's very weak and
> > as a microphone, the cable will late or soon break
> > because it is too small ;
>
> I've never had any problem with mine in the three years I've
> used it. I clip the speaker/mike to my shoulder harness and
> can hear it fine with the volume turned up maybe half way.
> I've been told that some early models were shipped with the
> audio gain set (internally) too low, so perhaps this was
> true
> at some earlier time.
I've seen Delcom radios with two different external
loudspeaker/microphone units. One (the biggest one) was
working fine but not the other one (the small square one).
I don't know which one was older type or new.
> As far as getting what you pay for, I'm not
> so sure. The $2,000+ German radios are ergonomically nice,
> but many of my friends with them have had to send them back
> for expensive repairs, usually more than once.
> Each of their
> repairs cost more than an entire new Delcom.
It seems that the most reliable of all German radios is
the cheapest one, with mechanical frequency selection
system and non electronic display...
In our club, we have some Terra. One got black frequency
display within one week. Back to the factory. We also have
a panel King. It work fine but is hard on battery. One
portable King (the most expansive of all portables) need
repairs within one year. No problem at all with Delcom,
except external microphone cable (we are planning
installation of gooseneck microphones, a must in any
sailplane).
J. Richard
Steven B. Wood
Contact Powersonic. They have a Webb Site. They have a large variety
of excellent battery solutions for glider type applications. Sealed
Gell Cell recharbale. I belive they have 14v systems. Have been
flying with them for years in my DG-400 which is power hungry.
Powersonic batteries have been reliable and are very moderately priced.
Good luck.
SBW
David Kinsell
Phil Stade <pst...@agt.net> wrote in article
<34e036b1....@news.calgary.telusplanet.net>...
> It has been suggested that my problems with a Radair 10S may be due in
> part to lack of voltage.
I had a 10S that was far enough off frequency on the main channel
(123.3) that it couldn't transmit at all to my handheld ICOM, yet was
close enough that most older radios could pick it up fine. A new
crystal solved that problem.
> I use a 12 volt 7.0 amp battery. Is there a
> reasonable solution to getting the voltage up to 14? Can two 12 volt
> batteries be connected and the resulting 24 volts reduced
> electonically to 14 volts?
Could be done, but not worth the effort.
A common setup around here is to add a 2V 5AH sealed lead/acid
cell in series with the 12V. These used to be sold as Gates X Cells,
I bought some equivalent units from a local battery dealer marked as
Hawker Energy Cyclon.
Wings and Wheels http://members.aol.com/DiscusEW/Bat.html
sells 4V and 6V packs that can be put together for 14V. Knauf
and Grove have some commentary on their site http://www.glider.com
that really isn't correct. 14V packs are used because most radios
are designed to be used with 12V batteries being charged by an
alternator, which runs just about 14V. Most radios will work
adequately on 12V, so some investigation into your problem
is called for. If your 12V pack is good, and it's being properly
charged, it's not at all clear that this is your problem.
Before you go adding cells, you should check that your 12V unit
is really good. Charge it, use it for a full day, then check the
voltage during transmit. Should be over 11V, preferably 12.
I always see people doing radio checks at the beginning of the
day, but what's really important is to see if it's still working at the
end. Rechargables frequently develop a high impedance defect
that lets them charge up to normal voltage, but it quickly drops
after minimal use.
> Would a solar panel continuously charging
> the 12 volt battery be sufficient to maintain a high enough voltage?
If it supplied the average current requirements of your system,
it could be made to work, but I'd go with 7 Cyclon cells or something
similar before trying that.
Dave Kinsell
remove any aquatic animals you find in my email address for correspondence
Jon Minhinnick
On Tue, 10 Feb 1998 11:21:19 GMT, pst...@agt.net (Phil Stade) wrote:
>It has been suggested that my problems with a Radair 10S may be due in
>part to lack of voltage. I use a 12 volt 7.0 amp battery. Is there a
>reasonable solution to getting the voltage up to 14? Can two 12 volt
>batteries be connected and the resulting 24 volts reduced
>electonically to 14 volts? Would a solar panel continuously charging
>the 12 volt battery be sufficient to maintain a high enough voltage?
Nobody's mentioned it yet, but why not put an adapted 12 V voltage
regulator in series with your battery? I understand that with each
diode between the reg's ground pin and the real ground, you will get
an additional 0.6V increase in the output voltage. (You'll need a few
capacitors as well). Of course, this is at the penalty of increased
current drawn from the battery. Go to your local electronics shop and
have a chat to the least spotty teenager you find. If they can't help
you, check a manufacturer's tech sheet for the device. Make sure the
reg. meets your current/power requirements, and it may need a
heatsink.
Unfortunately, I don't have any further information immediately
available. The information isn't hard to come by, though.
Hope this helps
>
>Thanks
>
>Phil Stade
>GPSS Canada, (spring is coming soon... isn't it?)
----------------------------------------------------------------
jo...@voyager.co.nz Ka 6 PE ZK-GBU
(To reply, remove the "nospam_")
Next time someone sneers at a wooden sailplane, remind them that
it is made of a unidirectional reinforced laminated composite
material consisting of micro-tubular fibres embedded in a long
chain polymer matrix and having a near infinite fatigue life.
-----------------------------------------------------------------
Nathan Lemmon
Sorry.......it just doesn't work that way. The 0.6V you mention is
the voltage "drop" across the regulator. Subtract that from the
voltage available to the radio............NL
John Giddy
Jon Minhinnick wrote:
> Nobody's mentioned it yet, but why not put an adapted 12 V voltage
> regulator in series with your battery? I understand that with each
> diode between the reg's ground pin and the real ground, you will get
> an additional 0.6V increase in the output voltage.
Not true ! Voltage regulators, of the usually available type at your
friendly electronics store, require an input voltage at least a couple
of volts higher than the regulated output. i.e. if you want 14 volts,
the battery supply needs to be about 16v.
There are DC/DC converters which can give you any voltage you like from
your battery, but they are not so easily available, and are much more
complicated and expensive than just adding an additional cell, if you
really want 14+ volts. I think the suggestions in this thread about
having the radio checked for tuning accuracy etc. by a suitable repair
shop is more likely to get results.
John G. (Retired electronics engineer)
--
John Giddy Mangalore Gliding Club
5/287 Barkers Rd http://www.gfa.org.au/vic/mgc/
Kew, Victoria, 3101
Australia "I'd rather be soaring"
Jon Minhinnick
On Tue, 17 Feb 1998 15:39:45 +1100, John Giddy <jgi...@melbpc.org.au>
wrote:
>Jon Minhinnick wrote:
>
>> Nobody's mentioned it yet, but why not put an adapted 12 V voltage
>> regulator in series with your battery? I understand that with each
>> diode between the reg's ground pin and the real ground, you will get
>> an additional 0.6V increase in the output voltage.
>
>Not true ! Voltage regulators, of the usually available type at your
>friendly electronics store, require an input voltage at least a couple
>of volts higher than the regulated output. i.e. if you want 14 volts,
>the battery supply needs to be about 16v.
Hmmm... I may stand corrected, but I'm not quite ready to just yet.
The reason I think this may be possible I believe is sitting in old
notes at my old job. I can't quite remember how the setup was. Perhaps
the diodes were zeners. Perhaps they were in a reverse polarisation. I
just remembered it was a configuration by which it fooled the reg's
feedback cctry into thinking it was producing that little voltage
less, thereby beefing its output voltage to compensate.
It was used in a battery eliminator that we manufactured, where a 6V
power pack was used to produce a 7.2 V output. Come to think of it,
the diodes were 1N4004's, which if my failing memory serves me
correctly, are signal diodes, and I *think* they were between the
output and ground pins. I should be able to confirm this in a day or
so after getting in touch with my ex-workmates. Stand by!
>There are DC/DC converters which can give you any voltage you like from
>your battery, but they are not so easily available, and are much more
>complicated and expensive than just adding an additional cell, if you
>really want 14+ volts. I think the suggestions in this thread about
>having the radio checked for tuning accuracy etc. by a suitable repair
>shop is more likely to get results.
And after all that, I'd tend to agree that the tuning is the best way
to reach optimum performance- otherwise, wouldn't it be like
turbocharging a car with a worn clutch?
>
>John G. (Retired electronics engineer)
>--
>John Giddy Mangalore Gliding Club
>5/287 Barkers Rd http://www.gfa.org.au/vic/mgc/
>Kew, Victoria, 3101
>Australia "I'd rather be soaring"
>
----------------------------------------------------------------
CWatters
Jon,
I'm afraid John Giddy is right.
Standard three pin linear regulators need an input voltage typically between
1V and 3V higher than the rated output in order to work correctly.
However you are not wrong...
You can turn a 6V regulator into a 7.2V regulator by adding a diode in
the right place (typically the 0V reference pin). However this will also
increase the required input voltage as well as increasing to output
voltage.
ie A 6V regulator needs 9V input.
A 6V regulator with 1.2V diode (=7.2V) needs 10.2V input.
3V is for standard parts
To get 1V specify "low drop out".
To get a higher output voltage than input you need to use a switching
regulator configured as DC to DC step up converter and some associated parts
(inductors, capacitors, sometimes FETs/transistors).
Some electronics distributors (mostly those that sell to the hobby market) sell
kits that do this sort of thing but I haven't checked availability to your
spec.
You will need to know both the voltage and the current drawn by your radio
as the DC-DC converter "trades" voltage and current in similar ratios.
ie Vin x Iin = Vout x Iout (plus some up to 50% losses in the conversion!)
For safety assume something like a factor of 2 as step up converters are
not very efficient (ie they may get hot)...
try Iin = Iout x Vout/Vin x 2
eg = 1A x 14/12 x2
or = 2.3A for every amp input
--
Colin Watters, Manager, H/W Technologies,
Acorn Ltd. Tel: +44 (0) 1223 725596
Acorn House, 645 Newmarket Road Fax: +44 (0) 1223 725696
Cambridge, CB5 8PB email: cwat...@acorn.com
United Kingdom WWW: http://www.acorn.com
Kevin Ferguson - AstirCS - 1U - ARS:ko0b
On Tue, 17 Feb 1998 01:44:45 GMT, nle...@cris.com (Nathan Lemmon)
wrote:
>Sorry.......it just doesn't work that way. The 0.6V you mention is
>the voltage "drop" across the regulator. Subtract that from the
>voltage available to the radio............NL
IF you have at least 16 V battery, then putting diodes in the _ground
leg_ (thus lowering the reference) of a 12V regulator WILL raise it's
12V output by ~.6V/diode. Not much good for running radio, as few have
so much exess battery voltage available, but might come in handy if
homebrewing a charger for 7 cell setup or some such. Actually, running
a 6V and a 12V battery of same capacity in series and regulating down
to 13.8 would be a much better setup than any of the 7 cell
cluster-f@#$s I've seen.
If you, or a friend, are serious electroniker, a LT1070 switching
regulator will boost 12V to 13.8 and deliver 4A or so without
complaint. That is how I run the radio in my Astir. Switching
regulators, however, can be difficult to get working, and if not well
filtered may generate interference to radio and/or instruments.
Linear Technology's application note for the '1070 is a work of art,
and if you follow all of Carl Nelson's excellent advice, it will work.
The '1070 was designed to do exactly this (or similar) function, so
app. note requires no interpretation....you want that app. note
anyway. You won't find anything but resistors for this project at
radio shack though....If you or a friend aren't a Digi-Key customer
already, then this may not be an appropriate project.
-1U-
-Kevin Ferguson-
"They that can give up essential liberty to obtain a little
temporary safety deserve neither liberty nor safety"
-Benjamin Franklin
John Giddy
Jon Minhinnick wrote:
>
> Hmmm... I may stand corrected, but I'm not quite ready to just yet.
>
> The reason I think this may be possible I believe is sitting in old
> notes at my old job. I can't quite remember how the setup was. Perhaps
> the diodes were zeners. Perhaps they were in a reverse polarisation. I
> just remembered it was a configuration by which it fooled the reg's
> feedback cctry into thinking it was producing that little voltage
> less, thereby beefing its output voltage to compensate.
>
Hi John,
I agree that you can increase the output voltage of a fixed voltage
linear regulator by putting diodes in the ground lead.
HOWEVER you can't get a higher voltage out of a linear regulator than a
bit less than the input voltage.
Remember the data sheet parameter: "Drop out Voltage" ? For commonly
available regulators this is of the order of 2 to 3 volts, and the
regulator will cease to regulate if the input voltage (from your
battery) drops below this 2 to 3 volts above the output voltage.
Therefore, if you want a 13.8 volt output, your regulator input voltage
must be at least 15.8 to 16.8 volts.
Regards, John G.