Sega monitor

[rookie]

As the name implies, a rookie here.

I have a Nanao MC-2000-S monitor. When I first got the game I did not have any manuals and the monitor was sitting free in the case not connected to the rest of the chassis because the previous owner had a cap kit installed. I powered it up not noticing the screen shield wire was hooked to the narrow/wide post on the main board instead of the neck board where it belonged. Probably OK till I joined the chassis back with the monitor frame, (oops) Blew the main power transistor Q901 and the small .8 amp fuse, but surprisingly not the main fuse.

[Ken Layton]

That Sega/Nanao manual is widely available to download from places like arcadehelp.com and bombjack.org

There are some electrolytic capacitors inside the flyback cage that when dried up cause vertical collapse/shrinkage. Perhaps a replacement got damaged?

There's also a fusible resistor in the vertical circuit that may have opened up.

[rookie]

Thank you.
I have a much better print now, I can almost read it.

My main power is down to 96 volts from the 105 listed with less than 1/2 volt AC on it, probably from changing the transistor.

[Ken Layton]

Check capacitor C523 (under the cage around the flyback) which is a 47 uf @ 50 volt capacitor.

Check fusible resistor R416 (near the flyback cage) which is 22 ohms, 1/4 watt. Also check the vertical output transistors Q401 and Q402 (they are generally both type 2SD1138).

[rookie]

Cool! got it!