Re: Flash Gordon problems rectifier board?

Stan,
One note - if you're measuring the rectifier board test points w/ the
board disconencted, you'll get readings that don't appear correct.

No problem w/ R1 being a little low and the +43VDC being a little
high. 44VDC will not hurt the coils, and the MPU reduces that down to
20-something for the zero crossing detector so that won't be a problem
either

Controlled lights running at 7.7VDC should not be a problem either.
the controlled lamps turn off every 1/120th of a second, so an extra
volt is not going to kill them.

15VDC off the bit honking diodes is no problem as that's the input to
the 5V regulator, so it'll take care of it. It's also input to the
MPU's Valid Power Detector, but I don't think a few extra volts will
matter there either. Your big C23 capacitor on the sole/reg board
should be rated at at least 25V - so it can easily handle 15.

Yes, both those big resistors get hotter then hell! When I repair
these boards, I raise these two resistors up a bit to allow for better
airflow. Board scorching under these two, plus the big diodes is
typical for the -54 rectifier board.

If your MPU did not get a good 11V and 5V input, you'd be getting ZERO
flashes, so I think your issues lie in the MPU board, as Tim
suggests. Read Clay's Bally guide on what the flashes mean, then try
to find out what causes a lack of 3rd flash, and take it from there.

http://www.pinrepair.com/bally/index2.htm#flash


steve
---
Steve Kulpa (cargpb10)
Hermitage, TN
http://www.geocities.com/stevekulpa/pinball.htm - Pinball
http://www.geocities.com/stevekulpa/faces/rgpidx.htm - Faces



On Jan 28, 11:13 pm, Pinballed <probass...@xxxxxxxxxxxx> wrote:
Ok, 600 ohm resistor...(R1) is measuring low, around 527 ohms. That
goes to  +43VDC. Which now measures a bit higher around 44.7VDC.  R2
is supposed to be 25ohms but it's measuring 27 ohms.That goes to the
Sw IL and according to my schematics should measure 6.5 VDC and is
currently measuring at 7.7 VDC. Also, the CR5,6,7,and 8 do whatever
they do and I'm supposed to get 11.9VDC reading on test point 3 but I
get more like 15VDC. The AC at test point 4 reads 6.7VAC so thats well
within proper limits so that's supposed to mean my transformer is
good. The 600 ohm ceramic resistor gets pretty freaking hot and looks
to have slightly toasted the board... I mean ever so slightly, but you
can see a difference in hue. Not worried the board's shot...it isnt
but that resistor probably is. My question is...can something as
simple as that resistor (600ohm at R2) running low and those diodes
and poss the bridge rectifiers all in conjunction there, screw with my
solenoid driver board, frying my C23 caps WAYYY to quickly and
therefore my mpu gets to 2 flashes and then says...FU to me?
Because thats what I HOPE it is for petes sake!  Sheesh. I was going
over the boards and such over and over again until FINALLY...just
yesterday the damn thing got to all 7 flashes and booted up ready to
go. Lasting for about 20 minutes...which gives me enough time to 'go
over' the other boards and do some tests and see that everything seems
to be functioning properly. Only to die out and go BACK to only giving
me 2 flashes (which makes the game useless to make sure all my other
boards are happenning...and all the test points are giving me either
proper or slightly higher than normal readings) and then I'm back to
square one scratching my head and screaming into my pillow at night.

Any help would be very appreciated

Stan

.

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