wg7xxx med res monitor - hv shutdown trim dripping/melted?

Cartouche

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wg7xxx med res monitor - hv shutdown trim dripping/melted?

I'm trying to troubleshoot this Wells-Gardner medium rez monitor in my APB. The screen is blank when I fire up the game. No static sound, no neck glow. Fuse tests ok. There is a noise almost like a cassette player eating a tape and light flickers that appear to be originating from under the chassis board, under the flyback.

I pulled the monitor to do an initial visual inspection of the chassis and noticed this syrupy shit I mean stuff that looks like it's coming from what the label calls the "hv shutdown". The stuff has dripped across a few resistors.

2 questions-

1. What does the hv shutdown do and what is this syrupy goo dripping out of it?

2. Do I measure the B+ voltage from the resistor on the left side of the chassis, outside of the metal frame near the flyback? Or is it measured from the one standing on its end on the right side?

Thanks,
Marc
 

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start at the beginning , check your input voltage and check the fuses. the "goo" you see is an expoxy they put on there so people do not screw with the B+
 
Thanks-
At the 2 slot molex connector that attaches to the monitor I get 123vac.

The B+ voltage reads 123vdc. And 159vdc at the other end of the resistor. Is 159 a little high?

No raster if I crank up the screen control.

When the game is powered, there is a burning/melting plastic smell that SEEMS to originate in the area of the flyback.

Bad flyback?

Edit: I am getting that static sound when I power up.
 
Here's some photos.

For the heck of it,I checked R213 for an open heater circuit on the neck board, it's ok.
The horizontal output transistor tested good too. (I'm pretty sure I did the test correctly.)

Not sure if this info helps shed some light, but when I try to discharge the monitor with a screwdriver at the 2nd anode, I don't get any "pop". I really pushed it in there, and made sure to come in contact with the metal prong(s), but nothing. Powered on and off more than once to try...
 

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try taking d10 out of circuit and fire it up , see if the pic comes up , if it does your reg is toast possibly . change c57 as well before replacing the reg , it may be bad and showing as a bad reg. just a couple ideas for you , failing that , cap kit time and flyback replacement time
 
Well, I guess I'll go the cap and possible flyback replacement route, as I am unable to unsolder a leg of the d10. It's completely encased in that hardened goop like a fossil in amber.

I took a look underneath at the solder joints and one of them under the flyback is pretty bad, smells like the source of that burning smell. And that white streak is not a photographic effect from my fast-moving pencil....
 

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