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Re: FM xmitters, was: Radio Reception

To: autox@autox.team.net
Subject: Re: FM xmitters, was: Radio Reception
From: GSMnow@aol.com
Date: Wed, 18 Sep 2002 22:45:33 EDT
In a message dated 9/18/02 5:18:34 PM Central Daylight Time, "Brian 
Berryhill" <bikepoet@netzero.net> wrote:
 
<< What kind of FM transmitters do "they" use at Nationals?  Any chance I 
could
 get in touch with "them" to ask some questions?  I did some research a while
 back trying to find one for our local club, but didn't get a lot of user
 input.  So, I assume I wouldn't go wrong with a system with the "good enough
 for Nationals" seal of approval. >>

I am not sure what SCCA National uses, but here in Chicago the TSSCC club 
bought a Ramsey FM25A a few years ago which puts out about 1/10th watt and 
uses a PLL controlled oscillator to lock it on frequency. With a good antenna 
on the roof of the van, we get well over 1/2 mile coverage and it is 
basically legal under FCC part 15. Our field strength is probably just a 
little over the true legal limit, but it is close. There is an adjustment to 
lower the power if you have the proper test equipment and a desire to be 
totally legal. We have not had any complaints yet. The sound quality is 
excellent. Chicago Region SCCA just bought the newer version FM25B which is 
actually a bit more powerful, and sounds even better, but they have not put 
up a good antenna yet. With the tiny whip inside the timing trailer the range 
sucks, even with nearly double the power out of the older unit. The legal 
limit is based on actual signal strength in the air, so more power is okay 
with a crappy antenna. We hope to have a good antenna on it soon, and then we 
may have to dial down the power a bit to make sure we don't get complaints. I 
tested it with a fair home built antenna and was able to get a full mile at 
max power out. 

If you don't care about FCC legality, Ramsey sells some "export only" kits 
with true output power of 1 watt, 10 watts, 50 watts, and more. Their units 
are covering complete islands in the Carribean.

Check out their web page
http://www.ramseyelectronics.com/

I have nothing to do with this company, except I have built and used 3 of 
their transmitters now. They all work great, which is more than I can say for 
some other units we have tried.

Gary M.

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