Transmitter Power Output SOMEthing to remember

[Multi-Volti Devices (Murray)]

Many rigs didn't have a tolerance on power output, but I think the SB-104
did -
+/- 1 dB, which worked out to about 20%...so the nominal 100 W output was
within spec even at 80 W, which we all know everyone would cry about.

I had one on the bench at Heath that I couldn't get more than 78 W out of on
one band...of course who knows how accurate the wattmeter was, but it
measured low, so we called it low.

A more experienced tech suggested I check power across the band as an
indication of bandpass alignment. It WAS in spec in some parts of the band,
not in others. The solution in that case was to replace some of the bandpass
filter components (all fixed value parts) by trial and error to 'tweak' the
alignment.

In my case the toroid inductors were no longer available, so we swapped the
equal-valued input and output filter inductors on a hunch and a hope that it
would skew the bandpass in the preferred direction - it did, bringing it
into spec.

That rig had SO many problems...I ended up spending a full week and half a
day on it - 44 HOURS! My boss wouldn't let me 'pull the plug' and declare it
unrepairable once I had 10 or so hours in it...he said just keep trying.
Everything I checked had a problem, but it wasn't my nature to skip
anything, because it would probably get sent back for one of those
complaints - that would be my luck., so it was perfect when it left, but
from that point on I renamed the SB-104  the SOB-104.

Bandpass alignment reminds me of something relevant to the question asked by
Jerry -

If the rig in question is a heterodyne oscillator rig, like an HW-100, 101,
etc, gosh, I guess that would mean anythin newer than a boat anchor
(multiplier vs. heterodyne oscillator), make ABSOLUTELY SURE you did NOT
cheat on the alignment - being on the 'wrong' side of an RF voltage
measurement peak, or only aligned in SSB vs CW portion of band,etc.

Murray

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