I know I'm going to figure this out only *after* I break down and ask for
help ... but I gotta ask anyway I suppose.
I have the K3/100 and an MH2 microphone and I am measuring output power with
a calibrated scope across a dummy load.
I have been setting up audio gain and compression as instructed (With comp
off set mic gain for 5 bars, then increase comp to fill in the waveform...).
I have always before observed that, with compression set to zero the peaks
of output come up to the power that I have set (or nearly so) but with
relatively little in between the peaks. With compression added the waveform
filled in at, more or less, the commanded output power. This is what I have
always expected but today it is not happening that way.
Today, for the first time in quite a while, I notice that what I had been
accoustomed to seeing no longer occurs. With compression off I can adjust
the mic gain for 5 to 6 bars ALC as usual but the peak rf envelope never
gets close to the commanded output of 100 watts. If I press TUNE the full
100 watt carrier appears but I cannot get peaks to rise much past 50 watts
with input from the mic. With compression the waveform fills in with RF but
the level is stuck at about 50 watts and ALC is still reading 5 bars or
more. It does not matter whether I have the audio chain set to High or Low
gain .. most of my testing has been with the usual "FP.L bias" setting but I
have tried High and also tried other microphones.
I notice that, after not speaking for a few seconds, if I make a sudden
sharp noise the output does spike up to 100 watts but is quickly clamped
down by ALC so that furthur loud sounds into the mic produce only about 50
watts. To make a long story shorter ... When SSB output is set for 100
watts I only get about half that even though the ALC is showing 5 or 6 bars.
The same is true with a setting of 50 watts or 12 watts where peak output is
about half of the setting and I am seeing 5 or 6 bars ALC. The audio sounds
fine in the monitor and signal reports are good. All of this occurs on all
bands and I see the full 5 or 6 bars ALC even in Test mode with no RF
output.
I'm running the latest 1.78/1.58 firmware which I downloaded last week.
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