Red Hot Radio

As it turns out, just like in audio engineering, in 2-way radio you can’t just look at the power meter and assume your signal is great. It might actually be unintelligible.

Back in my early days (6 months ago), I noticed that my RF power meter seldom hit 100W on voice. I know that the duty cycle of voice on sideband is significantly less than 100%, but even the peaks weren’t hitting it. Frustrated with apparently not getting my signal out of the region, I turned on the built-in audio compressor, tweaked the compression amount, and got that average power a bit higher to somewhere that looked right.

As I learned recently on the regional AARC 10-Meter Net (Sundays 3pm CT on 28.410MHz USB), my fellow net participants complained that there must be some RF feedback into my mic or something because my vocal peaks were seriously hot and distorted. They had been complaining for a few weeks, and I assumed it was some insufficient grounding in my car. While discussing it during a net, I mentioned that I had compression turned on; they asked me to turn it off, and the distortion went away.

Huh!

So, uh, remember that owner’s manual thing, and the part in it that tells the owner how to configure mic gain and compression? Yeah, so if I follow that, and look at the ALC (audio level control) meter instead of the RF power meter, and if I adjust things so the average and peaks stay within a specified range, then my signal should sound better.

I hooked up my dummy load, went to 10m sideband, spoke gibberish into the mic and tweaked the mic gain and compression amount to a range that makes sense (at least visually). I’ll try an A/B test on the next 10m net to see if it worked.

It’s not the output power that wins friends and gains contacts; it’s the signal quality. You can reach across the country on 10W if your antenna is good, the sky is right, and your signal is clean. Otherwise, you’re splattering your distorted RF energy across the band, you’re burning battery power, and you’re wasting someone else’s time.

Published by Shawn

He's just this guy, you know?