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It's 527 ohms? That's definitely a problem if the resistance is truly that high. I'd verify pin 8 of UJ6 has a good connection and then verify pin 4 of UE7 is good as well from underneath. If they look good, remove UE7 from the socket and inspect the IC itself along with the socket. if...

I just fixed a similar issue with the simasimac and happy chime. UJ6 ended up being the culprit, but you definitely have a problem in the video circuit. It's hard to tell what's exactly going on without a logic probe or oscilloscope. Check the continuity between the address lines and UJ6 then...

For anyone from the future that may have this problem, UJ6 was the culprit. I replaced it and now have a fully functioning SE/30.

There’s a replacement CRT available on eBay right now.

What would cause no activity on the VIDW line at UE6?

What does the clock signal look like on the probe?

Checked with the scope and I do see RAS/CAS go low. Checked VIDW with the scope and it’s always high.

Okay. Checked at the VRAMs for VIDW and got the same results. The LED just stays on for RAS, CAS, and DT-OE. So they’re just staying high?

I checked VIDW at UE6. It did a flash at startup (dimmer than UJ6 but a flash nonetheless) but afterwards the LED had no activity.

Just got a setup exactly like yours. When starting the computer it flashes bright immediately like yours does but after that I can see it flash but it’s extremely faint. So faint that it’s not even lighting up the bulb part and you can just barely see the diode glow.

I did it again and made sure I was on triggered mode. There is a little spike that comes down every few second. It’s pulsing something.

Thank you so much for the help you’ve provided. Know a good source for one of these ICs?

Rechecked and pin 12 has 5 volts. Rechecked the output and it doesn’t pull down.

Got continuity for every address line to the processor.

Would an oscilloscope work? When I probe pin 8 with that it doesn’t do anything. I see the line stay high but doesn’t ever come back down.

Just did that test with a random disk and it does take the disk, try‘s to do something with it, and then ejects it.

The PAL chips and VROM as they’re the ones that’s socketed. Yes at this point I am leaning towards a bad IC rather than something wrong in the circuitry.

I’m getting continuity to all pins on the VRAM. I’ll definitely get a boot disk made and try that. Sounds like a good idea. Will probably pick up an IC tester as I‘m leaning towards that being the issue.

Thank you. That explains a lot. I’ve got 5 volts and good ground at both vram chips. I can’t say they’re 100% good but I know they’re putting out some sort of signal. I’ve been checking all the traces like crazy and to my surprise have yet to find a single one that’s open. Do the PAL chips run...

I’m confused on which pins would supply power to the VRAM.