Ok, I got an idea to use an FM transmitter hooked to a microphone to make announcements to people cruising in our local car club. I know there is a way but I cannot find the site I was on...it told you how to modify your transmitter to give it a 200' range rather than the very low range weak signal. Does anyone know what is needed? External antenna? Replace some pieces with better ones...stronger power supply?

 

Both/either.

Be aware that altering some of these items are illegal and subject to the FCC's wrath. In my area we use FRS radios to talk back and forth along the runs.

Adding an antenna matched to the frequency will help a bunch. If you're talking about the 88-108 Mhz band you're talking about an antenna about 30 inches long.

I've seen amplifiers for FM radio transmitters that do no require a license for about $40 in some electronic kit stores. You'll have to soldier parts into a pre-made circuit board.

 

Yea...eventually we want everyone to have a handheld radio. They're not even that expensive...but people are stubborn.

 

I thought you might be rated in one of the electronics fields there Master Chief. I was an AT in AIMD Shop 610 on the Roosevelt, SeaOpDet out of Whidey for the EA-6Bs that used to be there. That was back during Gulf War 1.0 though so I'm a little rusty on my radios.

I think he's talking more of a broadcast system for the commercial FM band though so FRS won't work for him (unless he uses an FM synthesizer to alter the freq). He wants people to be able to tune into their regular FM dials and hear announcements but he doesn't want everyone chattering on his frequency.

As Paul stated though you're talking about pirate radio. The FCC probably won't come after you but you want to make sure you're not overdriving all the local stations 'cause that tends to **** off the people that paid for those bands.

Back to your actual question:

How much do you know about electronics? Can you solder? Have you ever done anything like building one of those Heathkit/Radio Shack kits? Don't sweat if you haven't, anyone can learn but it makes it easier if you have a little experiance. If not you will want to learn a bit about basic electricity and electronics. Radio Shack has some good material for learning that stuff.

Doing a quick search I found some ready made amplifiers that only require a little bit of work on your part. Here are some links to some of the items you might want to use:

3 Watt transmitter: http://www.quasarelectronics.com/1187.htm
15 Watt FM amp: http://www.quasarelectronics.com/1179.htm

You could use those with the FM transmitter you already found to up the output.

Those are from a British site, and probably aren't legal here, but should give you an idea of what to look for. You might want to look for stuff that runs off 12V so you can run it right off your car's aux power otherwise you will need a power supply and an inverter. Kind of a waste to bump the power up to 110V just to bring it back down to 18V though.

And finally FRS operates at about 500 milliwatts with an optimal line of site range of one mile and does not require a license. GMRS (General Mobil Radio Service) operates at between 1 and 5 watts, with a range of between 5 and 25 miles, and DOES require a license so think about what 15 watts is going to do.

 

Well, I can solder as long as it isnt a really cramped space...
I know basic electronics
And yea...I would stay on the channels that are allowed by the low range thingy cuz they arent used anyway... I already have a power inverter so thats not a problem.

 

Yeah, I was an ICmen - broadcast television NEC. I'm also a ham radio operator and dabble in ATV. Before I joined the Navy I was a custom car stereo installer. My primary hobby is firearms but a close second would be audio. I was stationed in Japan for five years (USS Midway) and spent a whole lot of time in Tokyo in the electronic's districts.

FRS radios are about $9 each in pairs at Chinamart. Batteries are not included. GRMS radios require a license for $70/5 years and are a bit more expensive at about $40-$70 each.