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Part 15 with FM transmitter
Recently I bought a Ramsey FM transmitter (FM25b) from Hobbytron. The RF output of this transmitter is rated to 25mW @50 ohms (at full power, however you can tune the power from 0-25mW). I install it using a simple dipole antenna (gain=1) feeding the antenna with about 125 feets of RG-6 wire (75 ohm ). Calculating the loss, my effective radiated power should be something about 8mW. I know that part 15 doesn’t specify antenna height and or ERP. Does this complies with part 15?
Preliminary test shows a coverage of about 2000-2500 feets from my antenna, using my car radio. I can receive the signal in full stereo the first 300 feets, then the signal begins to get very weak after that. I also try to receive the signal using my radio walkman, but the signal fade out about 400 feets (to much hiss and distortion from others FM stations).
Thank you for any information…Mickey
Total posts : 45366Sounds like a fun set-up.
You might have better results by placing the xmtr closer to the antenna and eliminating the 125 feet of cable. That takes away some of your transmitting power.
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