Williams Display Board (D11232-2)

[MartyJ]

Hi Guys,

I'm still working on my display from the PF.  Its out of the machine and I cannot test it at the moment, as I have exposed wires under playfield (lamps for bumpers)...  I have a new PinScore LED replacement on the way, BUT I don't want to give up on this one and still trying to getting it going.

Thus far, I've replaced R32 (resistor) and U7, U8, U9, U10, U11 & U12 (4049's).  They have been tested and DMM readings are in range (Clay's)...THe UDN6118A's are the same and all UDN7180's except U16.  On U16 pin 6 (or 6th pin from 1) I'm getting an nil reading.  I don't believe this is correct.

Last time I had it in the machine, only the 1st display (top) was working, 2nd (lower) was not on at all (only U12 replaced since then)

I still have a feeling that the SRC's for display on the CPU may have an issue, but I wont know for sure until the PinScore goes in...

[Retropin]

Hi mate,

Seems the previous thread got lost in the ether,

but pin6 and pin 7 on U16 are inputs from the address bus from either U8, U9,U10, these are fed from connector J3, didnt we have a zero signal from here somewhere?

[MartyJ]

Hi mate,

Seems the previous thread got lost in the ether,

but pin6 and pin 7 on U16 are inputs from the address bus from either U8, U9,U10, these are fed from connector J3, didnt we have a zero signal from here somewhere?

I was getting some strange readings from U7 to U11, so I replaced / socketed the lot.  I have a bit of an anomoly with Clay's guide for testing the 4049's.  Red to pin 8, black on 2-7, 9-12, 14-15.  On mine, U7, U9, U10, U11, U12 and two new ones are all getting null readings on pin 9.  However, on U8, I'm getting a reading?????

**Scratch that re U8.  Pulled out the chip and getting same reading.  Replaced it with another and now they are all the same....But still pin 6 on U16 null....Could this be a bad UDN?

[Retropin]

pin 9 on U8 is for the "dot" on display 2.

Connector J3 is split into 2 halves, pin 1 is ground, pin 2 is 5V logic, then pins 3 - 10 are all for display 2 - the rest 11 - 26 are for display 1.

The buffer chips have all been replaced, but, you say you put 4049 in there??

Schematic has them listed as 4050 which is non inverting - the 4049 is an inverter,
schematics clearly show these as definately non inverting, both listed and on diagram.

...I printed off the diagram for your machine as this part differs to my space station

Also do you have signal going into J3? - follow it back through connections. You have lost signals from somewhere either at this connector or before it. BUT, once you get the signal back, if the right chip is not on place at U8 etc, then all youll get is garbage displayed

[MartyJ]

pin 9 on U8 is for the "dot" on display 2.

Connector J3 is split into 2 halves, pin 1 is ground, pin 2 is 5V logic, then pins 3 - 10 are all for display 2 - the rest 11 - 26 are for display 1.

The buffer chips have all been replaced, but, you say you put 4049 in there??

Schematic has them listed as 4050 which is non inverting - the 4049 is an inverter,
schematics clearly show these as definately non inverting, both listed and on diagram.

...I printed off the diagram for your machine as this part differs to my space station

Also do you have signal going into J3? - follow it back through connections. You have lost signals from somewhere either at this connector or before it. BUT, once you get the signal back, if the right chip is not on place at U8 etc, then all youll get is garbage displayed

I initially bought 4050's (as per other thread), however on the board they were actually 4049's (original).  Clay has a note on his site with a disclaimer that the schematics have errors in relation to these..I checked the manual for the display board parts and it has them listed as 4049's.

I cant have the machine in a powered state at the moment until I put the new bumper lights in (exposed wires under playfield) and the last thing I want to do is kill the cpu board with a short!  I have it in front of me in front of computer with DMM trying to get as much done as possible.  IF the PinScore LED's work perfectly (then I can not worry about SRC's on CPU) and actually play and enjoy the game.  I'm just trying to get this working (a) for the challenge and to learn (b) get the damm thing working!

I've been though Clay's guide all day (finished doing U12 & U11) and it cleaned up real nice.  Previously I was not getting readings anywhere near what Clay suggets but now - all but U16 are looking good..

If there is not much else I can do on the bench, I will wait until I get the lamps done next week (when parts arrive) and will attack it again then with your advice!

[MartyJ]

Hi RetroPin,

I got a bit keen tonite and wanted to see if replacing all the 4049's had worked.  So, I scotchlocked the exposed G.I wires for bumpers & taped, double checked that nothing else was or could be exposed underneith then plugged display in & fired her up.  To my surprise, all three are now working.  I didn't run through the diagnostics as I didn't have enough hands but definately getting what appears to be correct on all!    Soo the good news is that it may look like the SRC's on CPU are healthy.  I was still getting some 'flaming' on the top alpha display (not sure what the correct term is) but I would bet that it is caused by the unbalanced +100/-100.

So hopefully I can pickup my PinScore LED tomorrow & put that in.  The better news is that this one survived and I've got a spare, or pick up a bargain somewhere (MarkC???!!) to put it in.  Taxi maybe or F14???!!  I've still got some plastics for one of those too!

[Strangeways]

Hi RetroPin,

I got a bit keen tonite and wanted to see if replacing all the 4049's had worked.  So, I scotchlocked the exposed G.I wires for bumpers & taped, double checked that nothing else was or could be exposed underneith then plugged display in & fired her up.  To my surprise, all three are now working.  I didn't run through the diagnostics as I didn't have enough hands but definately getting what appears to be correct on all!    Soo the good news is that it may look like the SRC's on CPU are healthy.  I was still getting some 'flaming' on the top alpha display (not sure what the correct term is) but I would bet that it is caused by the unbalanced +100/-100.

So hopefully I can pickup my PinScore LED tomorrow & put that in.  The better news is that this one survived and I've got a spare, or pick up a bargain somewhere (MarkC???!!) to put it in.  Taxi maybe or F14???!!  I've still got some plastics for one of those too!

Good stuff Marty...

More Pinball techs than collectors on this site

 

[MartyJ]

Hi RetroPin,

I got a bit keen tonite and wanted to see if replacing all the 4049's had worked.  So, I scotchlocked the exposed G.I wires for bumpers & taped, double checked that nothing else was or could be exposed underneith then plugged display in & fired her up.  To my surprise, all three are now working.  I didn't run through the diagnostics as I didn't have enough hands but definately getting what appears to be correct on all!    Soo the good news is that it may look like the SRC's on CPU are healthy.  I was still getting some 'flaming' on the top alpha display (not sure what the correct term is) but I would bet that it is caused by the unbalanced +100/-100.

So hopefully I can pickup my PinScore LED tomorrow & put that in.  The better news is that this one survived and I've got a spare, or pick up a bargain somewhere (MarkC???!!) to put it in.  Taxi maybe or F14???!!  I've still got some plastics for one of those too!

Good stuff Marty...

More Pinball techs than collectors on this site

 

Yep, its a great mix here!

I ran the diagnostics (display test) and looks like I'm missing the 'f' segment.  I believe this is controlled by U16?  Which may explain the strange readings from that with the DMM?  I will try to find one (maybe even s/h) just to complete the display and get it working 100%.

[Retropin]

Damn schematics!!! Youd be surprised how often this happens! Always best to have the board in front of you also!

Great news mate - REALLY good to hear you got it all working OK.

What can i say?? Well done mate