HW-101 Strangeness

[Richard H. Arland]

Hi Gang:

I'm in the middle of  reclaiming a HW-101 from the junque pile. Looks
are deceiving. This thing had an almost flawless front panel and knobs
(main tuning knob not withstanding). Electrically it is a basket case.
This has been a very slow restoration due to the multiple problems
encountered. At least four different "technicians" have been inside this
rig. (Has anyone ever seen a HW-101 MODE switch emit whiteish smoke?
Mine did for several minutes on at least three occasions. That's just
plain weird!)

I've cured a number of ills, and I am ALMOST (but not quite) through the
receiver alignment in the manual! Hey, it's only been 6  weeks, gimme a
break!

My current problem concerns the receiver breaking into oscillation on 15
meters when trying to align the Driver Grid and Driver Plate PC boards,
using the crystal calibrator signal (as outlined in the manual).
Initially, the ONLY band that would align was 29.0 MHz! All the other
would not peak up according to the instructions. Several of the coil
slugs were run completely out of their forms before any peak in S-meter
reading was noted. This led me to remove both these PC boards and check
the Silver Mica caps. Virtually every SM cap was out of tollerence, some
as much as 300%! This is the first time I've run into SM caps being this
far out of spec.

All the SMs were changed on both boards and the alignment went smoothly,
UNTIL, I got to the 15 meter segment. Here I can get a definate peak in
S-meter reading when I adjust the coils for that band, but additionally,
I end up with a very irritating oscillation or squeal when I approach
peak on the calibrator signal. I have retightened all the nuts, bolts
and lockwashers around all the PC boards holding things together. I have
checked for bridged solder connections. I've reheated countless PC
connections, in hopes of finding a cold solder joint. 15 meters is the
only band I cannot get to fully align. No other band exhibits that
oscillation/squeal.

Anyone got any ideas? I'm rapidly running out of hair to pull out!

73 Rich K7SZ

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