ID Sega Astro City Monitor & Help Troubleshooting

More importantly you don't want the replacements to blow again immediately so you should check that there isn't still a short on the chassis. If the pad where the middle leg of the transistor was shows a short to ground you should find what causes that short an sort it or replacing the transistor will be s waste of timeand money.

So the pads where 2nd transistor that I removed didn't show a short. I touched the black lead to the middle collector pad. Then touched the red lead to each of the emitter and base pads. No short. Photo attached. Anything else I should check?

You should check that the flyback doesn't have its primary winding shorted to the secondary winding. If you follow the trace from the HOT collector (middle pin) you'll see that it goes to a pin of the flyback. That is the primary winding. The secondary winding is where you have the ground pin.

Took the chassis off the plastic sled so I could do this properly. The primary winding is not shorted to the secondary. Good news! Here is a higher resolution photo of the same image in case you guys see anything else out of the ordinary (high res).

Anything else I should check? Or should I now just await that new 2SC4157 transistor?
 
Sorry for bumping my old thread. But someone on another forum messaged me about this asking me if this was fixed. This was fixed. And the monitor has been running great since. Here is what I did:
  • Replaced HOT
  • Replaced 2SC4157
  • Recapped the entire chassis for good measure
I had no idea what I was doing at the time. Still don't. There is no documentation on this chassis. I got lucky on this one.

Interestingly enough, I just acquired another MS8 (MS8-29FB) and it is dead too. But this one doesn't blow fuses. Will pull parts and start testing them this weekend.
 
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