Copyright: 1996 - 2024
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FM Band Transmitter Specs - RF Cafe Forums
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Below are the old forum threads, including responses to the original posts.
|-- Amateur Radio
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Post subject: FM Band Transmitter Specs Posted: Tue Oct
11, 2005 4:33 pm
Joined: Tue Jan 06, 2004
Sorry for posting in multiple places, but I
need this in a hurry.
Does anyone know exactly what FCC spec
governs the output of an FM transmitter? My application is for low power
(<1 W), and in fact will be covered by Part 15. However, I want to
know the real specification limits for THD, frequency accuracy, L-R
channel separation, S/N, etc.
I have spent a couple hours searching
the web and the FCC website but CANNOT find it!!!
Thanks a lot
guys (and gals, if applicable ).
subject: FM SpecsPosted: Wed Oct 12, 2005 5:23 pm
The FCC has only
a few real regulations for license-free ("Part 15") use:
than 100 mW power
2. inside the FM band, and harmonics down a reasonable
amount (I don't know what it is right off the top of my head.
The rest is up to you. If you want to make a crappy Part 15 stereo
transmitter with lots of distortion, poor frequency response, almost
no separation, etc. , the FCC won't quibble unless you go outside the
band or power limits. If you want to make a state-of-the-art DSP-based
stereo transmitter, the FCC won't quibble unless you go outside the
band or power limits.
Broadcast station limits are something
else. You might look at those for THD, separation, frequency response,
distortion, etc. if you want a baseline for comparison.
these answers are not what you were hoping for - but they do reflect
subject: Posted: Thu Oct 13, 2005 7:42 am
Joined: Tue Jan 06, 2004 1:51 pm
Thanks for the
infoGuest. Morton provided the documents I was loking for here.