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Re: Windows 7 config

 


I strongly disagree Scott... That's a recipe for disaster. Feeding wide band unsquelched noise to a modulator will cause the transmitter to over deviate. Remember the squelch noise out of a discriminator is half the bandwidth of the IF filter which means you have audio at 7.5 khz + coming out of the receiver.. Anytime I run flat audio, I always put a clipper/limiter circuit in line to prevent over deviation, and also to limit the audio bandwidth to 3 kilohertz maximum. Under FCC part 97 rules we are required to make sure that we use good engineering practices. Running raw discriminator audio straight into a transmitter modulator without any processing violates that rule. I've done that in microwave systems but that's a special case and you have the bandwidth to do it. In the crowded VHF/UHF bands, it's totally ludicrous to do so

Chris
WB5ITT?


That's the key here: Bypass as much of the radio's internal audio circuitry as possible - raw discriminator audio out, TX
audio directly to the modulator.

Scott

Scott Zimmerman
Amateur Radio Call N3XCC
474 Barnett Road
Boswell, PA 1553
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