The formula is:
y=b(subscript 0) times b (subscript 1)^(dB gain of antenna)
Restated:
Effective Radiated Power= Radio output power X constant^dB gain of antenna)
The constant is equal to 1.25992105. Finding the constant which is the base
of the exponent was the more complex task.
Example: Your radio puts out 4 watts and you are wanting to buy an antenna
with a 6 dB gain rating.
Effective Radiated Power= (4)(1.25992105)^6 = 16 watts.
If you were to buy an antenna with a 9 dB gain rating, then the effective
radiated watts would be:
Effective Radiated Power= (4)(1.25992105)^9 = 32 watts.
From http://home.inu.net/davidstua/radio.html
ERP in a nutshell: Transmitter power * feedline loss * antenna gain.
Every foot of coax has some loss. This must be calcucated into the picture
in order to obtain the true output power at the antenna.
If a length of line has 3db loss and your antenna gain is rated at 3db, you
have negated the gain of the antenna.
IOW 3-3=0.
In order to determine the actual line loss constant, there is another
formula which takes into account, the diameter of the inner conductor, which
material is used, the distance between the inner conductor and the shield,
and even the makeup of the dialectric, including thickness, surrounding the
inner conductor.
It's best to simply consult the manufacturer of the cable for the constant
to make the proper calculations with.
If you're going to be discussing radios at least get your facts right.
Handing out derived bullshit from self proclaimed experts in truckstops will
do no good.
For example, it is a pure urban myth that you MUST have your coax cut in 3
feet lengths.
For a single antenna, length of a coax has no meaning.
Unless you're going to run the cable several hundred feet or more.
For a properly cophased system, two antennas, you MUST have the lines at
equal length.
But still, it makes no difference if that length is divisbile by 3 or not.
Where did the 3 feet thing come from?
Some kind soul somewhere this comes from the fact that 3 feet is a precise
division of the wavelength of the CB band.
Bullshit.
Take a look in any CB sales store. Precut cable comes in 3,6,9, and 12 foot
lengths.
That's where the myth comes from.
A 50 ohm cable will be 50 ohm end to end regardless of length.
> Mad Dog" <lgs...@strato.net> wrote in message
> news:bg5l0f$kv1ci$1...@ID-71746.news.uni-berlin.de...
>> Most Transmitters and Amplifiers are rated using the PEP (peak envelope
>> power) measurement,
>> however a more accurate measurement would be found by using
>> the RMS (root mean square).
>> ERP or (effective radiated power ) is found by multiplying the PEP x
>> the Gain or (power multiplication factor) of a particular antenna.
>> PEP=RMSx1.414
>> RMS=PEPx.707
>> --
>> 714 Sandpile,
>> The Mad Dog wavin' good bye
>>
>
> The formula is:
> y=b(subscript 0) times b (subscript 1)^(dB gain of antenna)
> Restated:
> Effective Radiated Power= Radio output power X constant^dB gain of antenna)
> The constant is equal to 1.25992105. Finding the constant which is the base
> of the exponent was the more complex task.
Enough of the fucking cut and paste, St00pid. You know nothing about the
formulas you just pasted into your reply, don't act like you do.
PEP = RMS x 1.414 ?????
RMS = PEP x .707 ?????
I'm sorry but no such power statements are true.
PEP does not have the peak voltage relationship
ratios that your formulas suggest.
More accurately...................
RMS voltage = Peak voltage x .707
Peak voltage = RMS voltage x 1.414
Care to comment about the rest that you snipped out:
> For example, it is a pure urban myth that you MUST have your coax cut in 3
> feet lengths.
> For a single antenna, length of a coax has no meaning.
> Unless you're going to run the cable several hundred feet or more.
>
> For a properly cophased system, two antennas, you MUST have the lines at
> equal length.
> But still, it makes no difference if that length is divisbile by 3 or not.
>
> Where did the 3 feet thing come from?
> Some kind soul somewhere this comes from the fact that 3 feet is a precise
> division of the wavelength of the CB band.
> Bullshit.
> Take a look in any CB sales store. Precut cable comes in 3,6,9, and 12 foot
> lengths.
> That's where the myth comes from.
>
> A 50 ohm cable will be 50 ohm end to end regardless of length.
Are you going to tell me this is hocus-pocus?
In 1971 I passed the written test for a 2nd class FCC radio license.
Do you know what that was? That was the license that gave a person the right
to work on electrical equipment within radio and tv stations.
You did not pass the test by answering simple questions. You also had to
show how you how came to that answer.
I have been fully acquainted with CB radios since 1968.
I have run the full gambit of equipment in my cars. From magnet mounts to
fully cophased 102" stainless whips, with, and without linears.
Including mounting a CB on a motorcyle.
When it comes to radios my dear child, yes I do know what I'm talking about.
Even though what I showed above was copied and pasted, it was to show that
it was NOT my personal knowledge alone, but that of others as well.
But if you want to argue the point with someone who has more knowledge in
the area face to face, find yourself a good technician and let them explain
it to you.
You'll get an education, for once.
-snip-
Please don't post what you don't know. Thanks!
>> Enough of the fucking cut and paste, St00pid. You know nothing about the
>> formulas you just pasted into your reply, don't act like you do.
>
>
> Care to comment about the rest that you snipped out:
It was all cute and past. St00pid plagerized it. Why the fuck would i want
to comment on it?
>
>> For example, it is a pure urban myth that you MUST have your coax cut in 3
>> feet lengths.
>> For a single antenna, length of a coax has no meaning.
>> Unless you're going to run the cable several hundred feet or more.
>>
>> For a properly cophased system, two antennas, you MUST have the lines at
>> equal length.
>> But still, it makes no difference if that length is divisbile by 3 or not.
>>
>> Where did the 3 feet thing come from?
>> Some kind soul somewhere this comes from the fact that 3 feet is a precise
>> division of the wavelength of the CB band.
>> Bullshit.
>> Take a look in any CB sales store. Precut cable comes in 3,6,9, and 12 foot
>> lengths.
>> That's where the myth comes from.
>>
>> A 50 ohm cable will be 50 ohm end to end regardless of length.
>
>
> Are you going to tell me this is hocus-pocus?
I was repairing, tweaking CB gear back before the best part of you dribbled down
your mommy's leg. I first talked on a CB back when the latest model was a
Heathkit you built yourself that my now 80 yr old dad built himself. It
had one crystal :) And dad put up a tower with a 5 element Mosely
verticle.
My first moble rig had tubes in it since transistor CB radios had emerged
yet. Considering all this and that I've been a ham for going on 14 years
who has built his own J-poles, random wire long wires, and quad beams,
trust me when I say this to you that you -don't- want to get into a
discussion about antennas, feed lines, coax, RF, gains, or anything else
about a transmitter, receiver or related topics.
Oh come on now. Be truthful. You were just trying to pull a fast one.
You were attempting to represented the post as your authoring.
Shame on you.
It's called "Argument from Authority" and is one of the classic logical
fallacies.
"I must be right because I'm an expert because I've......."
http://www.xenu.net/archive/baloney_detection.html
Now show us the measurements, and the math. :)
Furthermore sir, your PEP formula is incorrect.
It should be:
(PEV*0.707)squared
PEP = ------------------------------- PEV=Peak envelope voltage.
R
Instead of relying on truckstop gained knowledge, you could at least search
the web first before posting erroneous formulas.
This way what he says will only be in his post not everone elses.
Oops. Next time I'll attempt english.
Mad Dog,
Why Pep instead of RMS? Because of the bigger numbers.
Or, "Mine's bigger than yours."...
'Doc
>
> In 1971 I passed the written test for a 2nd class FCC radio license.
> Do you know what that was? That was the license that gave a person the right
> to work on electrical equipment within radio and tv stations.
> You did not pass the test by answering simple questions. You also had to
> show how you how came to that answer.
Oh so on top of all your other lies, you've held an FCC radio license.
BWAAAAAAAAAAAAAAAAAAAHAHAHAHAHAHAHAHAH
If that were the case, you'd be EARNING a good living instead of sucking
the goverment tit, unemployed and living in a rusting out shitbucket
singlewide bitching about your bank charging you for having a negative
balance in your checking account.
You cut and pasted out that anntenna and feedline shit Bullis.
You're in a recreational CB news group and you want me to post mathmatical
equations? BWAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHAHAHAH
Am I missing something?
Best regards from Rochester, NY
Jim
"Meat Plow" <me...@x-anon.com> wrote in message
news:pan.2003.07.29...@x-anon.com...
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I hate to bust your bubble. 2nd class could operate an AM or FM station
subject to power limitations and not if it was directional. The 1st class
was required for the high power stuff and for television. I had my 1st
phone and 2nd telegraph plus radar in 1966. In fact, at the am-fm-tv
station I worked at (WROC, Rochester, NY) I had inadvertently been assigned
to radio after it went directional at sunset. I found out when I arrived at
the station that afternoon. Much to the chief engineer's relieve, I pulled
out the 1st class license which I had received in the mail earlier in the
day :)
Best regards from Rochester, NY
Jim (former P1-20-8429) (T2-20-594 - I think)
"Richard" <anom@anom> wrote in message news:bg6c9...@enews2.newsguy.com...
I am well aware of what you're saying, I did not feel it necessary to
include all the damned details.
But the ticket allowed you to work in those stations outside of being a DJ.
Even if it did mean under a 1st class ticket supervision.
73 from Rochester, NY
Jim
"Richard" <anom@anom> wrote in message
news:bg758...@enews2.newsguy.com...
An amateur radio operator with a tech license or above can build certain
types of radio equipment.
But for CB radio equipment, you definitely needed a commercial license to
work on them.
I believe Heathkit did offer a CB kit at one time but it was quickly pulled
off the market.
More than likely the FCC told them to check the regs before offering such
equipment again.
One of the guys in my senior high school electronics class only came to
school once a week to take tests.
He already had a full time job as an assistant chief engineer with WEBN
radio in cincinnati.
Graduated to chief engineer, and last time I saw him, he was in the
engineering staff of WKRC tv in cincinnati.
>This is interesting. I had a couple of Heathkits (amateur transmitters)
>back in the early 60s. The DX-20, DX-35, and DX-40 all took a crystal. I
>don't recall Heathkit ever having CB kits. Back then, you had to have a 1st
>or 2nd class radiotelephone license to even repair them, let alone assemble
>them. I know; I had my 1st class radiotelephone license, commercial
>radiotelegraph ticket, and radar endorsement by 1966.
>
>Am I missing something?
>
Yes you are. They did sell CB kits.
73 from Rochester, NY
Jim
<tn...@mucks.net> wrote in message
news:of8eiv86fklvbvaom...@4ax.com...
Busting Bullis's Bubble is a national past time now. Hell, it might even be
a sport in the next Olympic games. See how fast you can make St00pid stomp
his feet in anger.
-snip-
>Richard has apparently set the record straight. He states that they did,
>indeed, offer cb kits, but they were quickly pulled off the market. Likely
>they hadn't checked the rules. Obviously, you would have to tune the radio
>(get on center of the channel - they were individual crystals back when -
>tune rf and if) and that *did* require a 1st or 2nd class radiotelephone
>license back then. That was why I posed the question.
>
>
>73 from Rochester, NY
>Jim
They were not pulled quickly. I have two of them, and I wasn't even
looking for them. They are not rare.
"Jim Hampton" <aa...@frontiernet.net> wrote in message
news:hfFVa.8134$et4....@news02.roc.ny...
Let's put it this way, the FCC told heathkit to shelve the sales ok?
Since you're claiming to own a pair, how about posting a photo of them?
I'm sure a lot of people would like to see these urban legends.
Well if you go way back to his previous posts about not giving a shit
about Certified Scale Houses, or Certified truck inspectors, that means
as far as him being a certified FCC technician, we should do as he says,
IGNORE THE DUMB FUCK!!!!!!!!!!!!
> Let's put it this way, the FCC told heathkit to shelve the sales ok?
Oh...now it's come from "they were shelved"..to they were "TOLD to shelve
them"....typical. Anything at all to try to wiggle out of the fact that you
might be absolutely wrong.
> Since you're claiming to own a pair, how about posting a photo of
> them? I'm sure a lot of people would like to see these urban legends.
How many people have been waiting for YOU to back up ONE of your claims?
You're not too bright....but you've got nerve.
~Tony~
For you?.......... What's in it for me?........... Make an offer and
I'll think about posting a pic.
Wrong again, Doc. RF amps are rated in PEP so the user can operate them within
their specifications according to whatever mode he/she desires. For example, if
the user has a 100 watt amp and they want to run AM (only God knows why), they
would be limited to a 25 watt carrier. Or if they wanted to run SSB then they
are limited to the full 100 watts PEP. And if they want to run SSB-RC, DSB-SC,
DSB-RC, FM, PM, etc, then they can calculate just how hard they can drive the
input, just as long as they know the PEP output rating. Unfortunately, most
illegal CBers think that a 100 PEP amp can run AM with a 100 watt carrier.
Ignorance is bliss (or so they say).
-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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>Let's put it this way, the FCC told heathkit to shelve the sales ok?
>Since you're claiming to own a pair, how about posting a photo of them?
>I'm sure a lot of people would like to see these urban legends.
>
>
Not sure where you got the information that the F.C.C. told Heath to
shelve their CB kits. They sold them from the early 60's through the
late 70's. Guess it just took them 15 years to comply? Heath quit
selling their CB kits (along with T.V. and amateur kits) due to the
influx of cheap import equipment.
I posted a couple of pic's of Heath CB kits for you in:
alt.binaries.pictures.radio
One of the first and last kits they made.
> Subject: Re: PEP vs RMS vs ERP
> From: "Jim Hampton" <aa...@frontiernet.net>
> Newsgroups: misc.transport.trucking,rec.radio.cb
> Date: Tue, 29 Jul 2003 23:23:37 GMT
>
> This is interesting. I had a couple of Heathkits (amateur transmitters)
> back in the early 60s. The DX-20, DX-35, and DX-40 all took a crystal. I
> don't recall Heathkit ever having CB kits. Back then, you had to have a 1st
> or 2nd class radiotelephone license to even repair them, let alone assemble
> them. I know; I had my 1st class radiotelephone license, commercial
> radiotelegraph ticket, and radar endorsement by 1966.
>
> Am I missing something?
I don't know it's been so long ago. Maybe it was pre-assembled. I was
born in 55 so it's not too clear in memory. I can remember smelling the
smoke from solder flux so that's could be why I recall that the radios
were in some kind of kit.
Correct you are. I believe the Heathkit CB kits had pre-assembled
crystal frequency synthesizer units. This made them OK in the FCC's
eyes.
Credibility is in it for you assclown....
My credibility is just fine.
Why would I ever bother posting a pic of a radio
for the sake or any anti rec.radio.cb poster.
P.S. I hope you don't lose sleep over not being able to see this pic.
I won't lose any sleep over it, since the pics are all make believe anyhow.
Mopar...@hotmailnospam.com wrote:
> What's wrong with Heathkit?
>
if they went to smt d or d would be pissed...
> I have been fully acquainted with CB radios since 1968.
> I have run the full gambit of equipment in my cars. From magnet mounts
> to fully cophased 102" stainless whips, with, and without linears.
> Including mounting a CB on a motorcyle.
>
Then it will be easy for you to explain "fully cophased 102" stainless
whips". What class would be indicated by the call sign KQV4990?
And oh BTW, do you have a job yet? My guess you'll answer that as fast as
you answered the question about being currently employed. You didn't
answer at all.
Sarge
--
If it walks like a duck ....... you know the rest
So what's your call sign?
"Richard" <anom@anom> wrote in message
news:bg75p...@enews2.newsguy.com...
73 from Rochester, NY
Jim
"Wavking" <wave...@komkast.not> wrote in message
news:pXOdnUERYLa...@comcast.com...
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"Jim Hampton" <aa...@frontiernet.net> wrote in message
news:wle1b.105581$eL6....@news02.roc.ny...
In the post, he was stating that a commercial license was necessary for cb
repair. He also stated that hams could do what the wanted with their
equipment; therefore I believe he intended to state a commercial license was
necessary to repair cb equipment. It used to be that way; a first or second
class radiotelephone license (and I also believe a commercial telegraph 1st
or 2nd would also work as they had theory tests) was necessary to repair two
way radio equipment (other than amateur). The commercial licenses have been
watered down; there is now only the General Radiotelephone Operators
License. I know as I used to hold a 1st class radiotelephone license,
commercial telegraph license, and a radar endorsement. I now only hold the
GROL (as well as an amateur license). I can't help with the exact dates
that the requirements changed, however. I do believe that was nailed down
fairly close in one of the threads on rec.radio.amateur.policy.
Kind regards,
Jim
"Brett Hayes" <Br...@truckindesperado.com> wrote in message
news:ymh1b.5372$8d....@twister.nyroc.rr.com...
> It is for the HAM Bands. and that is what he was referring to.
>
---
Heathkit made several CB radio kits mostly during the 60's I believe.
I happen to have an unbuilt heatkit GW-32 CB base station still in the
box if anyones interested.
I believe he's talking about legal requirements. In which case, he's
right on both counts.
As a ham operator, I can legally build and operate my own radio
equipment. It is *not* legal to build and operatge your own CB radio.
As a ham, I can repair and modify my ham equipment legally. But if
anyone other the holder of a commercial radio license repairs or
modifies a CB radio, it's illegal.
It's true that a lot of unqualified peoplemodify CBs. That doesn't mean
that it's legal.
Dan
The license is no longer required for tv or am/fm broadcast radio either.
"Dan and Nancy Mahoney" <d...@webfolks.us> wrote in message
news:bksdkj$59krh$1...@ID-199721.news.uni-berlin.de...
ZBM-2 from Rochester, NY
Jim
"Barry OGrady" <godphre...@REMOVEhotmail.THIScom> wrote in message
news:gu93nvs4dt5rnqol6...@4ax.com...
> On Fri, 22 Aug 2003 01:29:00 GMT, "Jim Hampton" <aa...@frontiernet.net>
wrote:
>
> >For what it is worth, a commercial license has not been necessary since
> >sometime in the late 70s or very early 80s.
>
> For what?
>
> >73 from Rochester, NY
>
> 10-4 good buddy. Back at ya.
>
> >Jim
>
>
> -Barry
> ========
> Web page: http://members.optusnet.com.au/~barry.og
> Atheist, radio scanner, LIPD information.
> Voicemail/fax number +14136227640
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I dont wanna hear about operator error more than once.
____________________
"Jim Hampton" <aa...@frontiernet.net> wrote in message
news:CVtcb.445$ai3...@news02.roc.ny...
73 from Rochester, NY
Jim
"Bob & Patty" <bob_c...@yahoo.com> wrote in message
news:vn6lnb2...@corp.supernews.com...
> Thanks to the Fed's, we now have "qualified" techs in all corners of the
> country. Hell, they're in every truckstop out there or close enough to be
in
> one. Now I ask you, with all that "qualified technical prowess" why do so
> many cb's sound like shit?
>
> I dont wanna hear about operator error more than once.
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