Fred McKenzie wrote:

On CW it puts out a good solid
100Watts.. But on SSB it only puts out about 10W unless I whistly loudly
into the mic.

Jeremy-

I had two SB-102s and an HW-100 about 25 years ago. Neither had low
audio,
although there were numerous other problems.

From the wording of your message, I assume the radio did have good audio,
but
now doesn't, using the same microphone et cetera. As with most tube rigs,
the
first thing to do was to check the tubes. Your tester would probably have
shown up a problem that would have caused your low audio, even if it
wasn't a
conductance-type tester.

The microphone must be high impedance. If you are using a low impedance
microphone, you just might not have noticed the low output before.

Is the microphone from Heath? They supplied a hand microphone with a high
impedance ceramic element, similar to the Turner 350-C. If you happen to
have
a non-Heath microphone with a crystal element, it is possible the element
is
going bad. A Rochelle Salts crystal element must be kept at just the
right
humidity level. If it gets too humid, the crystal absorbs moisture and
dissolves. If it gets to dry, its "waters of crystalization" evaporate
and the
crystal turns to powder!

When you replaced resistors, did you refer to the manual for the correct
value?
Some of the old resistors can be misread. Mistaking red or yellow for
orange
in the third band, would make a ten-fold error.

Beyond tubes, microphones and resistors, there may be an electrolytic
capacitor
that has either developed leakage or has dried out. Most of the lower
value
capacitors are probably OK, but no guarantee.

If you have the manual, there are probably voltages marked on the circuit
diagram. It might help isolate the problem if you checked them with a
high
impedance meter.

73 & Good Luck
Fred, K4DII

Yes, I referred to the manual for the values of the resisters. To explain.
When i upgraded to General in 1997 or 1998, a friend donated the radio to
me in "non-working" condition.. and another friend fixed it. In his fixing
of the radio he said all he had to do was replace some resisters and it
started working nicely.

Upon closer inspection he didn't replace the resisters but he patched them.
As in he added a resister in parallel to the existing resister to get it to
the resistance it was supposed to be instead of removing it and putting in
a totally new one. What I did was take both out and put in a totally new
one on all of them i could find.

As far as i know the entier time i had the rig it was low on output on SSB,
but i didn't notice until i had had the rig for a year since i was a
tech-plus and used the rig only on CW.

First off I tryed the stock heathkit mic that i believe came with the radio
and it was even worse, it would barely put our 5 - 8 watts. I found a high
impedance amplified microphone that i wired up and hooked up to the radio,
which then got its output up to around 10 watts.. with peaks if i whistle
into it loudly. I read the manual and attempted to match the impedance of
the mics to what the rig wanted.

The capacitors is something i never thought about until i was reading your
message. I've restored a old AM broadcast band radio once and I had to
replace all the capacitors, but I never thought about it on the SB-102.




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