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![]() wrote in message ups.com... My question is this: so long as final output to the antenna is within the requirement of part 15 unlicensed operation, is part 15 unlicensed operation allowed within a band normally governed under part 97? Part 15 operation would easily cover a 30 mile radius on 80M. http://www.access.gpo.gov/nara/cfr/w...7cfr15_06.html Part 15.223 says in part... "Subpart C_Intentional Radiators Sec. 15.223 Operation in the band 1.705-10 MHz. (a) The field strength of any emission within the band 1.705-10.0 MHz shall not exceed 100 microvolts/meter at a distance of 30 meters. However, if the bandwidth of the emission is less than 10% of the center frequency, the field strength shall not exceed 15 microvolts/meter or (the bandwidth of the device in kHz) divided by (the center frequency of the device in MHz) microvolts/meter at a distance of 30 meters, whichever is the higher level." For CW operation, your bandwidth is zero for all practical purposes. You will therefore be allowed 15 uV/m at 30 meters. From this I made a very crude estimate of your allowed transmitter output power. Assuming your transmitter antenna is 100% efficient and radiates hemispherically, your transmitter output power is allowed to be no more than about 1.7 nanowatts (1.7e-9 watts). For ideal circumstances (0 dB receiver antenna gain, 100% efficient receiver antenna), you would get less than 5 uV at a receiver 400 meters away. I stress that this is for ideal circumstances. If your transmitting antenna is less efficient, you can run more power, but less of your power gets launched. How efficient is that antenna, anyway? On the other hand, your antenna may have some directivity which would further limit your power. This is making my head hurt. All that can really be said about this estimate is that, to be safe, you should not have much more than about 2 nanowatts output power unless you have the ability to measure the field strength according to regulations. Good luck with your project. 73, John |