Followup: WG-6100 deflection madness.

Update: A while back I was having trouble with a WG-6100 that would
give me the nice vector clatter, but no video, and an active spot killer.

Deflection board 1: Lots of clatter, no picture, spot killer on.
Bug - Cold solder joint on Q603
Fix - Resoldered.

Deflection board 2: Deflection-transistor-eater pulled from cold storage.
Bug - Would play fine for 30 seconds and then blow up a couple of
      transistors after showing half a screen for a fraction of a
      second.
Fix - D702 was inspected in-circuit and found to be open. Replaced.

After both of these fixes, each deflection board was put into the WG-6100
and powered up, and each gave the same results - nice vector clatter, no
video, and an active spot killer.

I finally got some insulators and tried, rather than swapping the
deflection boards, swapping monitor chassis. To my great surprise,
both deflection boards worked perfectly. (Although I've got a new
project now, namely adjusting color purity on the other chassis :-)

Swapping the deflection boards back into the first chassis, where they
didn't work the last time I tried them, also resulted in both boards
working fine. *huh* I blame the same gremlins that ate the Mars probe
on Friday. One of those things I'll never figure out.

One other update - plugging in a deflection board without plugging in
the degaussing coil will smoke fusible resistor R106. The monitor will
behave normally after R106 opens, so apart from the initial panic "hey,
I smell smoke" when it first blows up, you may not even notice you've
done it. If you've done this - or if you haven't, but notice a burn on
R106, it can't hurt to replace it.

Later,
Doug.

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