HX-20 Low Audio FIXED

[Al Waschka]

The cause of the low audio was indeed a coupling cap.  I looked at the
voltage on the V1 side of C7 and saw about 3-4 volts of audio.  On the
balanced modulator side, there was only millivolts.  That is why I asked
about the balanced modulator audio injection level.  Alright, I'm a
little impatient, but when there were no answers on that question this
morning, I just jumpered a 4 uf in parallel with the original 10uf.
WOW.  Now I have the same level of audio as carrier on CW.  I think a
trip to the radio store is in order to replace all the old
electrolytics.

On the low output side:

One person suggested that 40 watts may not be low.  Well, the manual
says 100 watts input.  I'm guessing that in CW the efficiency should be
about 70% so I was looking for about 60-70 watts out.

Another suggested changing the final.  I tried that earlier and didn't
mention it.  Power went down.  Which leads me to the third suggestion:

One person said their loading capacitors had changed value.  I'm on the
trail of that now.

Thanks to all on the reflectors who took time to read and reply if they
had any ideas!

73,

Al K5TAN

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