Sharp Image SI-325MR

Peale

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I pulled this from a Cruis'n USA a while back. A Sharp Image SI-325.

Shoehorned onto a U5000 frame/tube assembly.

Flyback obviously bad - huge cracks/burns, etc.

Due to the size of the replacement, I had to move some parts to the underside of the PCB. Nothing major, just some resistors and a cap.

Capped it. Most of the caps in the power supply circuit had their shrink wrap pulled back from the top, so it definitely needed it.

Lots of solder rework.

Held my breath, and plugged it in. It appears to be going into shutdown. No heater. I looked for a B+ adjustment, like you'd see on a U5000, but if it's there, it's hiding well...

I found schematics on Randy Fromm's site. But, any and all troubleshooting ideas are welcome. Like...from where do I meter the B+ on this monitor? What should it be?
 
Well, a lot of what is going on was my own damn fault. I forgot to solder the HOT back in when I replaced the heatsink. with it attached. I had to remove it to replace the flyback.

Soldered that in, fired it up, and now I get high volage, and a nice thread of smoke, coming somwhere from the vicinity of r901, but not actually FROM r901. Can't figure out what burned. Still nothing on screen. Blaugh.
 
I THINK that I have a bad Q701 - a BDX53C. Which, of course, I do not have on hand. Scouring dead TVs to see if I have anything even remotely compatible. The bigger question is...why did it fail?
 
this is that moment that we all hate - knowing that we can fix a piece of equipment with a .50 part...and not actually HAVING that part. :p
 
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