?"Note that as a rule of thumb the ratio of peak to average in male speech is about 10db."
Most tech literature indicates 14.5 db.? Other literature indicates 21.5 db.? ?They call that crest factor.? ( peak to average ratio).
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Point is, without basic ALC, your average power output on SSB would be through the floor.? ?That's assuming using just enough audio drive to? just drive the xcvr to say 100w pep out.? ?You can see that on any average reading wattmeter.
if u want true average, use an RF ammeter.?
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I experimented? with my 6 x band digital compressor, and even with the rls times as low as 20 msecs, it works pretty good, but isn't like a RF clipper.? ?Done correctly, you can get globs of talk power....and zero distortion...and have no alc showing on the xcvr.? ? The problem with RF clipping is..... the filters only remove the out of band imd, and not in band imd...so there is a limitation there.? ?Another method is to use ALC, but with a much faster rls time constant.? Done right, that will be distortion free...and just as effective as rf clipping.? ? And any processing scheme will work at an optimum level if preceded by a good audio compressor.? You need to feed a constant level? into the device/xcvr etc.? With a boom headset, the mic is a constant distance from ur mouth.? To kill background noise pickup, either a gate, multiband gate, or downward expander is used.? ?A noise gate is just a high ratio downward expander.?
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remember when? TV commercials came on....and just about blew u outa the chair ?? ?I looked at em on an SA....and what happened when the commercials came on,? is all the peaks dropped exactly .5 db? all the way from lows...to highs, (20 hz to 20k)... meanwhile the average increased by exactly 6.0 db...again right across the entire passband.? ? And that's on top of regular program material.?
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With ham radio ssb, on RX, we have AGC.? ?S meters are peak reading devices....they won't depict average power.? On the old drakes, from S3? to 60 db over S9 only increased the audio output by a mere 3 db.? It's all squashed flat.
And no, I don't advocate shorting out the alc on drakes. Back then, gear was expensive as is.
