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Technical Topics => Part 15 AM and FM Station Operation => Topic started by: Shortwave_Listener on February 20, 2022, 0024 UTC

Title: Questions about part 15 shortwave
Post by: Shortwave_Listener on February 20, 2022, 0024 UTC

I am interested in building a part 15 shortwave station. I would like to use the transmitter design in this video https://m.youtube.com/watch?v=4UGzL5FCcMM . I have a few questions about it. Is it possible to determine the power output, and how can I calculate how many microvolts/meter at 30 meters is it outputting? What antenna length is need to get 10000 microvolts/meter at 30 meters (the legal limit)? Approximately what is the range you can expect at 10000 microvolts/meter at 30 meters? I am going to use a 13.56 MHz crystal instead of 8 MHz. Correct me if 10000 microvolts/meter at 30 meters is not the correct limit in Canada.

Title: Re: Questions about part 15 shortwave
Post by: NJQA on February 20, 2022, 1429 UTC

This ISM band runs from 13.553 to 13.567 MHz - a 14 kHz wide bandwidth.  It won’t support more than one or two AM transmitters.

This doesn’t seem like a good idea.

* If you want to stay legal, your output power will only be a few milliwatts at best.

* You are going to be competing will all sorts of industrial noise emittters.

* You are going to be interfering with a number of established hobbiest beacons.