Forum Post: Idea to solve the lack of a microphone problem: Fm transmitter+mic plus people bring radios.

Okay, it is legal to transmit on "normal" fm radio frequencies at low power, up to 200 feet in range. So take a microphone and a transmitter (commonly available as consumer electronics, examples below available through amazon) then get enough people to bring radio receivers. Almost everybody has a receiver and they aren't worth much these days so people won't mind bringing them. One receiver might work for maybe 5 to ten people so only a fraction of people need to bring a radio (receiver). It would be satisfying to circumvent the rules of the 1% like this! Plus it could really speed up the general assemblies.

http://www.fmtransmitterreview.com/frequently-asked-questions.html#how_far_can_a_low_power

http://www.gate.net/~advradio/fcc.html (more info)

Example product (relatively powerful one) http://www.amazon.com/0-5-Fail-Safe-Long-Range-Transmitter/dp/B003FO4UHW/ref=sr_1_2?s=electronics&ie=UTF8&qid=1318385816&sr=1-2 Radios that are not FCC certified for operation cannot be legally sold so if it is being sold on amazon.com you would think it should be legal but maybe you should get one that can only do 0.1 watts (100 milliwatts) just to be sure it's legal.

The 250 microvolts limit can be converted into a power output for a given radiation pattern, such as for a basic dipole antenna with some physics but I forget how and google isn't telling me any answers .