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Stations over-deviating in FM mode

BC Coyote

Sr. Member
Oct 17, 2023
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I've been spending quite a bit of time on 26.805 FM lately. Conditions this past weekend were pretty good but I've noticed that A LOT of people using FM mode are over-deviating. That is, they have cranked the audio gain up way to high. Now on AM mode this might make you loud and proud, but on FM it just makes you a garbled noisy unlistenable mess. There was a station in upstate New York dominating the channel on Saturday morning with a huge but almost completely unintelligable signal. It's too bad because the guy would have sounded amazing with about half the audio level he was running!!
My 6666 in my car has an especially hard time with these over-deviated FM signals, and there's a lot of those radios out there in use.

So for those of you running FM, do yourselves a favor and keep the audio levels within spec..... if you're not sure where to set them use another radio or an online SDR to monitor your signal, and set the level where the audio doesn't distort. On FM mode you're actually much better off with less audio than more, quite the opposite of AM and SSB. And remember, there's no swing in FM mode, it's all carrier.
 

not into fm just yet cause all i hear is static
 
not into fm just yet cause all i hear is static
You will need to use the squelch when in FM mode. It tends to have loud static but once a signal is received the audio will be much cleaner than AM or SSB...... That's just the way it is !
 
I run on FM occasionally and turn everything down to 50% of what I run for pep on SSB, so my 8 pill gets run around 600watts on FM, my 4 pill runs at 300 watts. Everything seems to stay nice and cool running there. The guys trying to get every last watt on FM will sound like crap and smoke their boxes in short order.
 
I run my 1X4 at 125 watts on FM. The same 125 as my AM deadkey. Adjusting for a higher transmit on FM can/will stress and pop transistors as you are essentially raising your AM DK. I don't even touch my box swapping to FM because there's nothing to change. Your AM deadkey IS your FM transmit when running a box, or at least should be.
 

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