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At @techknight 's suggestion, I opened up the neck board to see if there was some controller logic there. There's a lot going on here, but he suggested checking B+ on the sync processor TDA4858. I soldered some 24AWG wires to pins 3-6 and put the neck assembly back together. I connected a...

I put the monitor back together enough to test and the symptom didn't change. So CL43 being a bit out of spec wasn't the issue. I have more caps on order and will be testing and/or replacing some of the transistors in the horizontal circuit next.

Thanks for the info and link. I'll figure it out eventually. At the moment I'm thinking it's an out of spec capacitor or maybe a marginal transistor in the horizontal circuit. And yeah feel free to reuse the cap list. It's rare enough that I feel motivated to spend some time on it even if it's a...

The secondary power caps all tested fine. I replaced those I had in sock while I wait for the others. I did find that CL43 (a bypass cap on the QL20 emitter pin) in the horizontal circuit was 22% out of spec. Not sure if that's enough to cause this problem but replaced that and CL6. I...

I was lucky enough to find an AppleVision 850AV 20" display in nice condition. It does power up, but only kind of works at 1024x768 @ 60Hz. Most other resolutions or sync rates that it's supposed to support result in a distorted narrow raster. Hopefully it's just some electrolytic capacitors on...

Nope. I'm still on my first chamber liner and filter actually. I'd still recommend a Melitta-style coffee filter to use for the chamber liners and filters from another soldering equipment manufacturer that are the same size or larger and just cut/stamp them to the size needed for the Metcal...

Thanks so much @XodiumRetro !! That dump is identical to the one I posted previously, so that rules that out as the culprit. I guess the next step will be going back to check my work on the board. Ugh!

Here’s what It’s doing at the moment. Theres no change if the top cover micro switch is activated.

I programmed a ROM, popped it in and put everything back together. It didn't blow up which is nice, but the head is just clicking and lights are flashing on and off. Anyone know what this means? I'm still suspicious that the ROM dump may be corrupt. @Mac84 Would you be willing to dump one of yours?

Thanks @retr01! The 28-pin ROM needed 33 trace repairs. All but two needed 40 AWG wire to make space for the socket pins. It was fiddly work but kind of fun to do. I got the replacement ROM and ROM eraser. The eraser I ordered has a euro plug which is weird. It came via Amazon next day...

This is going to require trace repair for almost every ROM pin.

@retr01 no helpful markings that I see.

There was a lot of crust on the ROM pins! I used a USB rotary tool to scrape away the crud down to the shiny metal. A couple more pins broke off in the process. I soldered some leads on and by some miracle was able to get it to dump. the ROM dump is attached here, but not sure yet if it can be...

I was having a lot of issues with glare and sharpness. I recall @Branchus saying he had similar issues but just had to keep fussing with it until it looked good. No amount of fussing with mine could get it looking as good as his. That might have come down to the reduction lens. Consider getting...

Well, this isn't good. It looks like the cap managed to leak all over the ROM. I managed to get it out of the socket while only breaking two pins. I'm hoping it'll work well enough to dump. Fortunately replacements are cheap.

I've had an Apple Thermal Transfer printer on the shelf waiting for repair for a while and decided to dive into it. It powered up but then something started smoking. Uhoh! It looks like at least one electrolytic capacitor (C27) severely leaked and may have damaged a nearby ROM. Before digging...

I also have the Amscope trinocular on the boom stand. I bought it during a Black Friday sale of there's a couple of years ago. You may want to considering waiting a bit to see if they do that again. I have the HC210 camera and really do not like it, but am not sure which options would be much...

Just a little follow up on this. I did end up recapping the AC adapter, but it was still dead and I wasn't sure what was wrong. I ended up getting a generic adapter with the same specs that worked fine. Here's the display running..

Is there a resource for common failure points and adjustment of the tray loader drives? I have one that isn't successfully reading discs. I assume the laser power pot needs adjusting and/or the drive needs a recap. It's pretty fiddly so was hoping to find a teardown and repair guide before...

Yeah it works. I might have hit those pins when removing the sticker on top of the IC.