Tech: Gun Fight graphics problem

[bert...@gis.net]

I've found a few old posts about this problem before, but no answers.
Also, I saw a Gun Fight on eBay several months back with the same
problem, so it can't be too unique.

Basically, my Gun Fight works perfectly, except that about 75% of the
time, four or so thick, vertical bars appear over all of the
characters/obstacles. They look like jail bars or picket fences. I
couldn't find any info initially about this problem, nor could I solve
it myself. I've played the game for almost a year now, telling myself
and others that those bars just simulate a fence that the players are
hiding behind. I'm not fooling anyone, not even myself, with that one.

Does anyone know how to solve this issue? I can replace parts, I just
don't know what parts might need to be replaced.

[me...@austin.rr.com]

you might find some info .....
http://users.erols.com/mowerman/midway.htm
http://www.ionpool.net/arcade/midway/midway_8080_test.pdf#search='Standardized%20Test%20Procedure%20for%20Midway's%20Processor%20Boards'

hope one helps

[big dog]

Hi,

You could change out all the ram, 2107 rams...I have some at
www.arcadechips.com.

Mark Capps

[BrentRadio]

send it to Alex

http://www.elektronforge.com/

<bert...@gis.net> wrote in message
news:1128372537.6...@g49g2000cwa.googlegroups.com...

[Alex Yeckley]

> send it to Alex
> http://www.elektronforge.com/

Thanks for the reference!

> <bert...@gis.net> wrote in message
> news:1128372537.6...@g49g2000cwa.googlegroups.com...
> > I've found a few old posts about this problem before, but no answers.
> > Also, I saw a Gun Fight on eBay several months back with the same
> > problem, so it can't be too unique.
> >
> > Basically, my Gun Fight works perfectly, except that about 75% of the
> > time, four or so thick, vertical bars appear over all of the
> > characters/obstacles. They look like jail bars or picket fences. I
> > couldn't find any info initially about this problem, nor could I solve
> > it myself. I've played the game for almost a year now, telling myself
> > and others that those bars just simulate a fence that the players are
> > hiding behind. I'm not fooling anyone, not even myself, with that one.

It might be a bad connection between the game PCB and the sound board
(which is plugged into it at a 90-degree angle). From what you've described,
it's a problem with the data shifter, which is located on the sound board. If
the connection is not the problem, then it might be one of the data shifter ICs,
which are essentially unobtainium. They have to be recycled from un-loved
Midway PCBs from the same era.

Alex
----
ayec...@elektronforge.com
www.elektronforge.com

[bert...@gis.net]

Some great advice in here - thanks everyone.

I haven't had the chance to take a look at these things yet, but I did
note your mention that the data shifter would likely be the problem and
that it's located on the sound board. I've also found that I have very
flakey sound lately - could there be any relationship at all between
the two issues? What differences are there between the soundboards
from that era Midways? Could I just replace the entire board, and
possibly make some changes, and clear up everything?

[Alex Yeckley]

> I've also found that I have very flakey sound lately - could there be any
> relationship at all between the two issues?

Possibly, but probably two separate issues.

> What differences are there between the soundboards
> from that era Midways? Could I just replace the entire board, and
> possibly make some changes, and clear up everything?

The sound board (technically the "game PCB") is different for
each game. The motherboard is essentially the same, aside from the
software. You'd have to replace a Gun Fight sound board with another
Gun Fight sound board.

Alex
----
ayec...@elektronforge.com
www.elektronforge.com