What is the maximum power output for an FM radio transmitter?

March 12th, 2012

Question by : What is the maximum power output for an FM radio transmitter?
What is the FCC rule, without a license, in the US, the maximum power output for an (88-108MHz) FM radio transmitter?

Best answer:

Answer by Daniel K
From Wikipedia:

——————————————————————————–

Part 15 rules are quite strict for FM, making it nearly impossible to operate a legally-unlicensed station that can be heard more than a few yards away. The rule is a signal strength of 250 µV/m at 3 meters from the antenna within the band 88 to 108 MHz, set forth in 47 CFR §15.239. Radiating cable antenna systems do allow for longer, if still narrow, radiated fields and are commonly used for building broadcast systems (stadiums, dormitories, apartments, etc…) with high success. Such systems are also used for specialized audiences for hearing assistance and language translation at events. Some communities have attempted to have multiple Part 15 stations align to form a sort of neighborhood “syndication” and legally increase the outreach, but it becomes impractical in light of the new technologies which allow for information to reach a wider audience more efficiently.

I think that ends up being less than 1 watt. If your power output is over 1 watt, you definitely need a license.

http://en.wikipedia.org/wiki/LPFM

What do you think? Answer below!

Posted by admin

One Response

  1. RICH says:

    In simple terms, your limit would be 100 mw. or 1 tenth of a watt….(That might get you a few hundred feet..with a good antenna, a bit more.)

Trackback URL for this entry

%d bloggers like this: