Tech: Flash Gordon sound issue

[p***@gmail.com]

Hello,

My wife and I just bought our first pinball machine, a great old Flash
Gordon. It worked fine for a week or so, then sometimes when turning
on the power the sound just wasn't there. Turning off and on again
once or twice would correct it. After a week of this the sound stopped
completely. The game still comes on and plays, just with no sound.
When the game is turned on it does make a "bump" kind of sound at the
very beginning.It also looks like there are some lights not lighting
up, but I guess I'm not positive about that. I've already read lots of
good info on this forum and from the Marvin site about sound issues,
and I've tried some of the repair suggestions, to no avail. I've
checked the main volume pot in the coin door, and the trim pots on the
S&T board, and all are good. Turning the main volume pot all the way
up gives some white noise/static. I've looked over the S&T board, and
everything looks good. There were however some dirty IC chip pins and
sockets (the black film stuff), so I cleaned them all off. I
resoldered the big pin connector, and I ordered and replaced the
TMS2200. Still no sound. I'm not sure where to go next. Any info is
greatly appreciated.

Phil

[pindemonium]

Post by p***@gmail.com
Hello,
My wife and I just bought our first pinball machine, a great old Flash
Gordon. It worked fine for a week or so, then sometimes when turning
on the power the sound just wasn't there. Turning off and on again
once or twice would correct it. After a week of this the sound stopped
completely. The game still comes on and plays, just with no sound.
When the game is turned on it does make a "bump" kind of sound at the
very beginning.It also looks like there are some lights not lighting
up, but I guess I'm not positive about that. I've already read lots of
good info on this forum and from the Marvin site about sound issues,
and I've tried some of the repair suggestions, to no avail. I've
checked the main volume pot in the coin door, and the trim pots on the
S&T board, and all are good. Turning the main volume pot all the way
up gives some white noise/static. I've looked over the S&T board, and
everything looks good. There were however some dirty IC chip pins and
sockets (the black film stuff), so I cleaned them all off. I
resoldered the big pin connector, and I ordered and replaced the
TMS2200. Still no sound. I'm not sure where to go next. Any info is'
greatly appreciated.
Phil

Phil-
Usually when the sound in my early SS Bally pins act-up, just
reseating the socketed chips gets my sound working again. The "bump"
and "noise" you're getting through your speaker are good
indications-- I'd carefully re-seat all the IC chips and confirm that
no chip legs got bent, broke off or just making poor contact.

As you probably already know, FG is a great early SS machine with
merciless outlanes.

Steve-o
...living in total pindemonium

[p***@gmail.com]

Ok thanks. I'll give it a try and see how it goes.

Phil

[cody chunn]

Is your sound board a SoundsPlus or Squawk-N-Talk? If it's a SnT, what does
the LED do on the board when you power it up?
--
-cody
CARGPB4

Post by p***@gmail.com
Hello,
My wife and I just bought our first pinball machine, a great old Flash
Gordon. It worked fine for a week or so, then sometimes when turning
on the power the sound just wasn't there. Turning off and on again
once or twice would correct it. After a week of this the sound stopped
completely. The game still comes on and plays, just with no sound.
When the game is turned on it does make a "bump" kind of sound at the
very beginning.It also looks like there are some lights not lighting
up, but I guess I'm not positive about that. I've already read lots of
good info on this forum and from the Marvin site about sound issues,
and I've tried some of the repair suggestions, to no avail. I've
checked the main volume pot in the coin door, and the trim pots on the
S&T board, and all are good. Turning the main volume pot all the way
up gives some white noise/static. I've looked over the S&T board, and
everything looks good. There were however some dirty IC chip pins and
sockets (the black film stuff), so I cleaned them all off. I
resoldered the big pin connector, and I ordered and replaced the
TMS2200. Still no sound. I'm not sure where to go next. Any info is
greatly appreciated.
Phil

[p***@gmail.com]

Is yoursoundboard a SoundsPlus or Squawk-N-Talk? If it's a SnT, what does
the LED do on the board when you power it up?
--
-cody
CARGPB4

Hi Cody,

Our machine has the Squawk N Talk. On power up, there is a quick
flicker, then 4 flashes. I've read that no 5th flash means replace the
TMS5200, which I did, and the problem remains.

Thanks,
Phil

[cody chunn]

No 5th flash means that there is a problem with the U8 circuit, but not
necessarily the U8 itself. IMO, no work should be done on any board until
you are reasonably sure an item is actually bad. Just going on a suggestion
you read somewhere and replacing components can actually lead to more
problems instead of resolutions. OK, off the soapbox.

The controller microchip "talks" to U8 via the PIA at U7. If U7 is socketed,
you can swap it with either U10 or U11 on the MPU board as a test. You might
want to install both U7 and U11 from the sound board into the MPU to verify
they both will pass bootup. If the controller 6808 or 6802 is socketed, you
can also swap it out for a quick test, but you won't find on e of those on
the MPU.

If swapping chips doesn't indicate anything, you really need to send the
board out or get a logic probe and learn how to troubleshoot Data and
Address lines and chip control signals.
--
-cody
CARGPB4

Post by p***@gmail.com

Is yoursoundboard a SoundsPlus or Squawk-N-Talk? If it's a SnT, what does
the LED do on the board when you power it up?
--
-cody
CARGPB4

Hi Cody,
Our machine has the Squawk N Talk. On power up, there is a quick
flicker, then 4 flashes. I've read that no 5th flash means replace the
TMS5200, which I did, and the problem remains.
Thanks,
Phil