Tech: TZ DMD issue. Flaky images then blank.

[mike]

Not use to DMD issues so I guess I have been lucky...Turn game on DMD
looks perfect, about 10 seconds later it starts to get shaky, 10
seconds later its starts going haywire. I see three of everything, a
few seconds later they all start to fade until DMD is blank. Done
this a few times and the same sequence repeats itself...Reseated the
small ribbon cable to DMD.

Any ideas? Rebuild power supply? Any other connectors to reseat?

Thanks
Mike

[Lloyd Olson]

I tried emailing you earlier Mike and can't get to verizon right now. It
bounces back.

Here is what I tried to send -

Hi Mike

I'd turn the game off, reseat ribbon cables a couple times from CPU to DMD
driver board to DMD. Anything socketed on DMD driver board and CPU, gently
push on and be sure they are in tight. Look at IC's and see if legs are
tarnished.

Then see where you are at.

LTG :)

P.S. When it's out, measure votlages at big connector on DMD, that will help
you know where to go next.



"mike" <bills...@verizon.net> wrote in message
news:98cd9bd6-2e33-41f5...@i8g2000yql.googlegroups.com...

[Joe S]

Sounds like the DMD driver board has components that heat up and
fail. Look at the high-voltage components on it. Repro boards are
available if you're not into board work.

[Chris Hibler]

I would love to see a YouTube video of that Mike.
You may have a power problem, as LTG points out, but without measuring
power and without a little more info, it's tough to say.

Here's how to measure power...
http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#Testing_DMD_Controller_Power

--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball.htm
http://www.PinWiki.com - The new place for pinball repair info

[schudel5]

"mike" <bills...@verizon.net> wrote in message
news:98cd9bd6-2e33-41f5...@i8g2000yql.googlegroups.com...

Could be display itself of HV section of the display driver board (lower 1/3
of the board). Do you have another WPC game or DMD display you could swap
parts to see if it's the display or driver board?

--
Mike S.
Kalamazoo, MI
Gameroom: http://tinyurl.com/yxzavc

[mike]

On Jul 12, 7:51 am, "schudel5" <schud...@yahoo.com> wrote:
> "mike" <billsfa...@verizon.net> wrote in message

wish i did....4 other pins but no b/w games....gonna test voltages and
reseat all cables

[schudel5]

"mike" <bills...@verizon.net> wrote in message...

>wish i did....4 other pins but no b/w games....gonna test voltages and

>reseat all cables.

Any of your other ganes have a standard DMD display? Could at least check
that...

[mike]

On Jul 12, 10:20 am, "schudel5" <schud...@yahoo.com> wrote:
> "mike" <billsfa...@verizon.net> wrote in message...

other pins....tftc, avatar, stargate, godzilla godzilla, xfiles...not
sure what i can use

[schudel5]

"mike" <bills...@verizon.net> wrote in message...

>other pins....tftc, avatar, stargate, godzilla godzilla, xfiles...not
>sure what i can use

The standard DMD display that you have in Avatar can be swapped in to at
least checked to see if it's the display. You have to physically remove the
DMD from the speaker panel and reconnect it into TZ.

My guess though is that it's the HV section of the driver board. Look at
the bottom 1/3 of that board in the backbox and see if any components looked
burned, particularly the diodes and resistors. ED at GPE had HV rebuilt
kits for the WPC boards for $6 I think. It does take some time and
expertise to replace the components and test the traces to make sure
everything is good.

[Chris Hibler]

On Jul 12, 9:46 am, "schudel5" <schud...@yahoo.com> wrote:
> "mike" <billsfa...@verizon.net> wrote in message...

I would lean toward this being a power problem too, except for the
"three of everything" comment in the OP. I've seen two of everything
before, but never three of everything. I can not recall the root cause
of the two of everything problem but RAM failure would be a prime
candidate.

--
Chris Hibler - CARGPB #31
http://www.Team-EM.com

http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

[mike]

> Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/index.htmhttp://www.PinWiki.com- The Place to go for Pinball Repair Info

voltage numbers at dmd:

-120
-109
key
gr
gr
4.8
11.7
67

[Chris Hibler]

> > Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/ind...The Place to go for Pinball Repair Info

>
> voltage numbers at dmd:
>
> -120
> -109
> key
> gr
> gr
> 4.8
> 11.7
> 67

Those voltages are fine.
For reference, the -120 and -109 should be 12 volts apart. There may
be some rounding error there.
Regarding the video...change the viewing permissions on it so everyone
can see the video.
The video shows what I believe to be a logic issue on the DMD
controller. I've seen something similar to that, but not exactly.
There is a row logic IC involved.

Just to be sure, move the DMD from your TFTC or Avatar to your TZ
(whichever is easier...both should work). This will isolate the
problem to either the DMD controller or the DMD itself. If it turns
out to be the DMD controller, send it to your favorite board
repairman. DMD controller repair is a bit of an art as there are a LOT
of 74XX chips in the mix. If you'd like me to fix it, I certainly can.

But isolate it to the board or the display first.
--

Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm

http://www.PinWiki.com - The Place to go for Pinball Repair Info

[mike]

> > > Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/ind...Place to go for Pinball Repair Info

> Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/index.htmhttp://www.PinWiki.com- The Place to go for Pinball Repair Info

Thanks for all the help from everyone. Restores my confidence in RGP.
My update is confusing but its working again. I put the video of it
acting strange on youtube.

I noticed the continuity on my fuse did not seem great. It seemed the
top fuse was not toning out all the time. I replaced fuse and also
noticed the 2 lower screws that hold dmd power driver board in place
had almost backed all the way out and board was very loose. I re
tightened them down, new fuse and it seems to work perfect now??? I
thought I read somewhere the screws help ground the boards? Anyway it
seems to be working. If it fails again Ill suspect the board.

Mike

[mike]

On Jul 12, 6:05 pm, mike <billsfa...@verizon.net> wrote:
> On Jul 12, 5:02 pm, Chris Hibler <ch...@Team-EM.com> wrote:
>
>
>
>
>
>
>
>
>
> > On Jul 12, 1:19 pm, mike <billsfa...@verizon.net> wrote:
>
> > > On Jul 12, 11:21 am, Chris Hibler <ch...@Team-EM.com> wrote:
>
> > > > On Jul 12, 9:46 am, "schudel5" <schud...@yahoo.com> wrote:
>
> > > > > "mike" <billsfa...@verizon.net> wrote in message...
> > > > > >other pins....tftc, avatar, stargate, godzilla godzilla, xfiles...not
> > > > > >sure what i can use
>

> > > > > The standardDMDdisplay that you have in Avatar can be swapped in to at

> > > > > least checked to see if it's the display.  You have to physically remove the

> > > > >DMDfrom the speaker panel and reconnect it intoTZ.

>
> > > > > My guess though is that it's the HV section of the driver board.  Look at
> > > > > the bottom 1/3 of that board in the backbox and see if any components looked
> > > > > burned, particularly the diodes and resistors.  ED at GPE had HV rebuilt
> > > > > kits for the WPC boards for $6 I think.  It does take some time and
> > > > > expertise to replace the components and test the traces to make sure
> > > > > everything is good.
>
> > > > > --
> > > > > Mike S.
> > > > > Kalamazoo, MI
> > > > > Gameroom:http://tinyurl.com/yxzavc
>
> > > > I would lean toward this being a power problem too, except for the
> > > > "three of everything" comment in the OP. I've seen two of everything
> > > > before, but never three of everything. I can not recall the root cause
> > > > of the two of everything problem but RAM failure would be a prime
> > > > candidate.
> > > > --

> > > > Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/ind...to go for Pinball Repair Info

>
> > > voltage numbers atdmd:
>
> > > -120
> > > -109
> > > key
> > > gr
> > > gr
> > > 4.8
> > > 11.7
> > > 67
>
> > Those voltages are fine.
> > For reference, the -120 and -109 should be 12 volts apart. There may
> > be some rounding error there.
> > Regarding the video...change the viewing permissions on it so everyone
> > can see the video.
> > The video shows what I believe to be a logic issue on theDMD
> > controller. I've seen something similar to that, but not exactly.
> > There is a row logic IC involved.
>

> > Just to be sure, move theDMDfrom your TFTC or Avatar to yourTZ

> > (whichever is easier...both should work). This will isolate the

> > problem to either theDMDcontroller or theDMDitself. If it turns
> > out to be theDMDcontroller, send it to your favorite board
> > repairman.DMDcontroller repair is a bit of an art as there are a LOT

> > of 74XX chips in the mix. If you'd like me to fix it, I certainly can.
>
> > But isolate it to the board or the display first.
> > --

> > Chris Hibler - CARGPB #31http://www.Team-EM.comhttp://webpages.charter.net/chibler/Pinball/ind...The Place to go for Pinball Repair Info

>
> Thanks for all the help from everyone. Restores my confidence in RGP.
> My update is confusing but its working again. I put the video of it
> acting strange on youtube.
>
> I noticed the continuity on my fuse did not seem great. It seemed the
> top fuse was not toning out all the time. I replaced fuse and also

> noticed the 2 lower screws that holddmdpower driver board in place

> had almost backed all the way out and board was very loose. I re
> tightened them down, new fuse and it seems to work perfect now???  I
> thought I read somewhere the screws help ground the boards? Anyway it
> seems to be working. If it fails again Ill suspect the board.
>
> Mike

problem came back so must be something on the board that is
failing....Ill swap with a new board or get this one repaired...