Ok im at a loss, I replaced almost everything, I did not replace the caps (just did that, they test good 220mfd) nor the 5w ceramic resistors (tested good in spec) nor the .1 500v ceramic disc caps they tested 102nf/110nf/112nf.

Still not working.

I read somewhere the negative voltage should be 12v dc off between the high voltages.

I am getting on the dmd P1 -92vdc and -114vdc the schematics say -90vdc and -110vdc a difference of 12vdc. The 5vdc was around 4.97.

The controller power in was repinned and getting 5v

When I plug in the dmd q5 and r1 on the dmd power supply heat up quickly...

Everything else was replaced...

I must be missing something like an elephant.

Anyone have any ideas???

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I just read on the pin wiki "As shown in the table above, if DMD controller power is not connected to the display, the nominal 12VDC offset will be about 20VDC."

I may have a dmd issue instead of a supply issue...

Dmd is blank not even a hint of life.

But it seems to be shorting or stressing the dmd power supply. (Power supply is heating up, where it does not with dmd disconnected).

Which is my reluctance is tossing the dmd in fishtales or indy. Just got those two fixed and reliable LOL

The more I read I am leaning to an issue with the dmd controller (stern) or the display panel itself.

Perhaps a cap shorted open and is dragging the voltages down stressing out the dmd supply.

?

How would I know if the issue is the dmd tube or the controller itself without screwing up my other pins?

Or is that just a chance I take?

I think I will pull the dmd and check the controller and tube. I think something failed on the tube and/or the controller.

Due to the heating up of the transistor and r1 5w resistor... Like its drawing a lot of current and killing the d4 diode and stressing the mje15030 transistor. R6&7 were bad one was open the other was out of spec.

Untill I get a replacement I guess I should check the dmd and controller for bad parts.

Noone really has ever posted much for this controller... But my suspicion is something is shorted on that assembly.