There are a few issues with the monitor. The owner told me the spot killer was on, I didn’t even try it myself. R100 and R101 had burned up and been replaced in the past. These can be bypassed per Atari. I checked the resistance and R101 was good, but R100 was failing and was up to about 50M of resistance.

In the HV cage – there had been a grease explosion at some point. I was able to get the HV diode apart. One side was clean – but the board side connection was in pretty bad shape.

This is after the first round of cleanup. I was going to remove the boots and solder the diode in directly, but I kept cleaning the bad one and it had a solid connection under the crud. I used the meter and tested ohms through to the coil and nothing seemed loose inside.

Received a cap kit and a new HV diode. I forgot to get a pic of my replacement. One spring was junk and the other had disintegrated. My solution was a stiff replacement spring from a pen. I curled the leads on the diode to match the pen spring that I trimmed down to about 1/4″ and soldered them to the leads. I put it back in the boots and used a little RTV sealant to secure the boots into position. Since the kit came with a transistor set, I replaced them even though the originals tested good. Testing around the board showed R100 was failing so I removed it and R101 per the Atari service document. 3 of the fuses were the wrong ones – fixed that too. One of the capacitors wasn’t connected. Someone had cut the original on the parts side and then soldered a replacement to the lead sticking up. That solder joint failed. So weird..

I test caps as I take them out AND put them in just to see if there are any bad ones. I couple were out of spec – but nothing too crazy except the one that wasn’t connected at all.

Monitor fired right up! My first vector CRT repair. The picture was jumpy when I first powered it on, Deoxit on the pots cleaned that up. I picked up the B&K HV probe and tested the HV circuit – perfect 14.5KV.

15V2000 – Picked this one up at a friend of a friends house

Came out of an Asteroids Deluxe. Monitor was dim in the center of the screen and brighter at the edges and it had a big blooming issue..

More often than not, recapping, cleaning and reflowing pins on these chassis gets them back into working order.

It appeared the blooming was just a loose diode – this was not the case. Once cleaned and rebuilt, the deflection board seemed to work – but I could not get HV to move above 7KV.

Spent a lot of time in the red area trying to determine why there was nothing going on. I’d checked the resistance on HV transformer and all coils matched up vs. a known good one. However I was getting ~50v on P900 pin5 and ~200 on Pin3. Learned a lot about how this all works on this one.

But I had missed seeing this (this is with flash – it was a lot less noticeable) Bad HV transformer – makes perfect sense now.. Swapped one in and the monitor worked. Resistance didn’t seem to matter in this case.

One last item, you could flex the board and it would cut out and the spot killer would come on.. I pushed around the board and it was all along the outer edge.. I removed and reflowed all the wires and it slowly got better and more localized as things got reflowed. This particular board has some surface oxidation on everything.

The last little spot was here.

This did not immediately break. I reflowed the pins for all of these diodes – tried the board and the spot killer came on and stayed on, good! Poked them all again and D502 finally broke apart.

Chassis works!

19V2000 #3 – Monitor in from an operator

F600 had finally blown at some point, but many of these burned up.

After washing, a fiberglass pen does a good job of removing all the soot marks and cleaned up the mess as good as it can get.

All of these were replaced plus the two bottlecaps Q608, Q609

Monitor works!