Sharp Image SI-727R-DS: Retrace lines, no video

Tithis

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Few weeks ago I picked up a $50 Sharp Image SI-727R-DS, a 27" cga/ega monitor.

At first it looked like I was getting nothing, but turning on the screen knob I got a dark gray raster with retrace lines, which is something. Turning my test pattern generator on and off changed the lines, so sync seems to be getting through just fine.
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Messing the color drive, bias, contrast, sub brightness and brightness did nothing.

It has a MM1203N, which has the same pinout as this schematic from a similar sharp image monitor.

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Brought the multi meter out.
All VCC Pins: 12.3v (chip wants 10-13.5v)
Input pins have voltage around 1-2.6v, changing as I change test screens
Contrast pin goes up to 5.8v when contrast pot is maxed out
Sub-brightness and brightness pots didn't change anything
output voltage seems to be stuck at .23v, didn't change no matter what I did

Right now I'm thinking this chip is just dead. When I get home tonight I'll hook up the scope the clamp gate to make sure it's getting a pulse. Anything else that jumps out to check to anyone?
 
Did a better job tying the V and H sync together and was able to get this picture. This is with things pretty cranked up.

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I am not seeing any pulse at the clamp gate at all, but I am seeing the combined sync signal coming in at C711. I guess I'll follow it to pin 14 and see where it disappears. Maybe one of the transistors is dead or something.

edit: So I was looking for another ground for the other oscilliscope probe to start chasing the sync/clamp signal... and found this. R769 per the schematics is supposed to be a 22M 1/2 resistor between G2 and B+. And it not like some of the bypass caps which were clearly never installed, this has leads of one that was installed but cut off.

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Poked around the clamping circuit and found that R713 was open. Replaced it and we're back in business besides that funny business up top.

I did order a cap kit for it a couple of days ago, maybe that will help.
 
Made a slight mistake, I have a SI-727S-DS, not a SI-727R-DS

Slight differences in showed up when doing the cap kit.
C109: 33uf instead of the included 22uf
C392: Not included in cap kit, was a 22uf 50v cap by IC1003 (had one leftover from a G07 kit thankfully)
C907: was actually labeled, its the 4.7uf 50v BP by the flyback the kit says in unmarked

Looking pretty good now. That fold at the top was just with my TPG, once I hooked it up to my PC everything was fine *shrug* Much sharper image than the 25" currently in my upright MAME cabinet.

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