Cinematronics xy monitor issue

[hatrick]

I've got the Cinematronics monitor in my Armor Attack very close to working, but the vectors just do not line up properly. At first, it would work occasionally, now it looks like this all the time. The transistors on the heatsinks have been upgraded to 2N3716/2N3792, the voltage regulators replaced, R118, R119 R218 and R219 have been replaced with 47 Ohm, 5W resistors, and solder re flowed at all connectors.

Any ideas where to look next?

 

[modessitt]

Are you sure this is a result of the monitor?

 

[hatrick]

A friend tested the board on his armor attack machine, and it was working. Maybe it's time to test the board again just to be sure something didn't get hosed on the board since it was last tested.

 

[DogP]

You probably should check the voltage(s) at the PCB... the board could work fine in someone elses cab if their power supply is adjusted properly and yours isn't. That does look more like a board problem than a monitor problem though. Is there any sort of test screen/mode that might give you some patterns?

DogP

 

[DogP]

Well, since editing my post doesn't work, I wanted to also add this:

Speaking from an electronics standpoint, and not as a Cinematronics expert, it appears that one of your Y digital DAC lines isn't working, which is why you're getting overlap, and they're consistently spaced. That could be a faulty ribbon cable, bad solder joint, or maybe bad driver chip on the PCB (or affected by bad voltage).

DogP

 

[hatrick]

You probably should check the voltage(s) at the PCB... the board could work fine in someone elses cab if their power supply is adjusted properly and yours isn't. That does look more like a board problem than a monitor problem though. Is there any sort of test screen/mode that might give you some patterns?

DogP

I'll double check the voltage, but last time i checked it was right on. The second picture is the test pattern. It sort of mimics the building layout for the armor attack monitor overlay.

 

[DogP]

Heh, we posted at just the same time... I looked closer at your pics... I just wanted to post to make sure you saw my addition.

DogP

 

[hatrick]

Thanks for the reply, I'll look at the schematics and see if I can find what may be wrong.

 

[Mark H]

LF13331N


mh

 

[hatrick]

LF13331N


mh

Thanks Mark. Is there any way I can test the LF13331N short of ordering a replacement?

 

[hatrick]

Working now. Turned out not to be the LF13331N. I swapped he DAC chips and it started working. I guess one of the DACs just needed reseated. Who woulda thunk?