From Newsgroup: rec.games.pinball

keskiviikko 17. marraskuuta 2010 klo 17.38.08 UTC+2 WarpZoneArcade.com kirjoitti:

On Nov 16, 2:51 am, wozzer <wozzer2...@yahoo.co.uk> wrote:

Hi,
Can anyone help? I have a solid green led on my Bally -35 mpu, when I
short pin 39 & 40 on U11 the board resets, but then if I switch it off
and switch it on again the led is then off although I still have my
12v ok and the playfield lights up but nothing happens until I short
pins 39 & 40 again then it resets ok with the led still off I might
add.

Are you sure you're not shorting pin 39 to 40 on U9 and not U11?
If you're saying that the game boots and plays when you short pin 39
to 40 on U9 then you have a reset problem. I would suggest installing
a Dallas DS1811. You can find instructions in Clay's guide (pinrepair.com/bally).

There is no corrosion on the board, I have swapped U11 and U9 for
working chips and they make no difference. I am unable to swap U6 as I don't have another set of game proms. The game is an Elektra. I have metered most of the reset circuit and it seems ok, has anyone come
across this before?

It's pretty clearly a reset problem (IMO) so known good chips won't
help you because the ones on the board are good. Again, assuming a
manual reset makes it boot and play.
I sell a little daughter board that plugs into J5 and replaces the
EPROMs as well as adding a Dallas reset circuit. Here's an example.
The latest version includes reset:
http://warpzonearcade.com/?p=356
Send me an email if you're interested but you probably just need to
rebuild your reset section or replace it with a DS1811. Unless you
really do mean U11 in which case I'll have to rethink my answer ;)

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