Star Wars HV repair: R18 & misc

I'm in the process of trying to get my old Star Wars game fixed. It
has been broken for *13 YEARS*. Interesting story that I'll save for
a web page...

Anyway, I have searched the Internet for every source of information
I can find to try to get it working again. Right now I have the
classic "no video, but game sounds and controls are fine". It has no
HV transformer on it at all, a Wintron is ordered. I have replaced
the MPSU07 and BU406D even though the originals tested fine. I have
recapped the HV board, and got the +30V / -30V on the deflection
board working again. I haven't received my voltage regulators yet
(VR2 is blown wide open.) Hopefully I will have just a few simple
questions to get it working again:

1) Using the schematic, I am checking all the resistor values on the
HV board. Everything checks out to spec, except for R18. It is
supposed to be 33K, but in circuit it is testing at nowhere near
that. I pulled it out of the circuit, and it DOES test at 33K. I
put it back in and it is really low again. I am concerned about it
because it was the only resistor I checked that responded this way.
All the other ones tested correct without pulling them.

2) When the VR2 blew, it lifted up all three copper traces about 3mm
off the board. When I press them back down I get continuity on the
pin holes. Can I just solder them back down or do I need to run a
jumper wire to the next hole down the trace for each of the 3 pins?

3) I do not understand how to check the voltages coming out of the
power supply on the floor of the game. I have the schematics but
just can't make sense of it. I also don't understand how to know
whether I am supposed to be checking for DC or AC voltage - it seems
some pins have DC and some AC? Every fuse in the game is fine and to
spec, checked at the holders. Sorry I'm so ignorant, but I'm eager
to learn! I don't even know if I should be worried about the power
supply...

4) Do I really need to pull and check every diode? Or at this point
should I just replace VR2 (with insulator), install the new Wintron,
and try it out?

Interestingly, the only parts I have found and confirmed to be bad
are the VR2, and W1 (0 ohm jumper) on the deflection board. Could
the failure of these components (W1, VR2, and the HVT) be related?
Should I be looking at something else before turning the machine on
again?

Sorry if this all has been covered, I have only read 3 years worth of
archives so far...

Thanks everybody!
Jonathan Stanley

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Received on Wed Mar 12 16:07:17 2003