Dead WG K7400. Any ideas?

[rgbmatt]

Hello all!   First time posting here, but I've read through these boards for info in the past.

So I was on my way home this evening when I noticed an RGB monitor sitting by the side of the road.  Of course I had to put it in my trunk and take it home!  It seems to be a Wells-Gardner K7400 monitor in a very nice black steel housing.  There are a couple of extra PCBs inside: what looks to be a composite->RGB converter and a voltage regulator PCB for powering a 12v fan, but aside from these the hardware is exactly the same as the arcade model.

And of course, it doesn't work.  The monitor doesn't power up; it just makes a repetetive clicking sound like a relay going off.  There appears to be one baked disk capacitor on the board, but I can't see any other obvious problems.  Unfortunately, the case design makes it near impossible to poke at the board while it's powered on.

Any idea what's going on?  This is a gorgeous monitor and I'd hate to let it go to waste.  I see that WG sells replacement deflection boards for ~$200, but it'd be nice if it could be repaired for less than that.  I do have a bit of experience with monitor repair, but the "completely dead" nature of this one makes it hard to know where to start!  Any advice would be greatly appreciated.

Thanks in advance,
Matt

[menace]

Flyback failure maybe.

[Ken Layton]

You can always contact the tech support dept at Wells-Gardner. The k7400 is a current production model (standard resolution).

It could have a shorted horizontal output transistor and/or bad flyback. This chassis uses a builtin switching regulator power supply. Get out a capacitor meter and check all the electrolytic capacitors. Randy Fromm has a troubleshooting guide for the k7400 on his Super Secret Technical page (www.randyfromm.com).

[rgbmatt]

Thanks, Ken - that's just the info I needed .  I'll try working on it a little tonight and we'll see how it turns out.

I've got high hopes that the fried capacitor might be the cause of the short-circuit - if so, that'd be great since it'd cost next to nothing for a replacement.  Hopefully the flyback is still OK (it is a rather recent monitor after all).