Recent content by jonschultz

I’ve never really heard much of a noise from a CC’s degaussing coil, so I think it’s just the case that they’re designed for pretty low current and are pretty weak. You might just try multiple power cycles and see if that helps to improve the spot. The main power button is what initially powers...

I have a partial schematic of the AB around the video section here: https://github.com/jonschultz/colorclassic_video_processor/blob/main/CC_analog_video_section_20260513A.pdf I'm pretty confident in the component values (the ones that I have), though I don't have the tolerances. If you have any...

I checked out your KiCad project. Very impressive! At some point I hope to pull the trigger on getting one of these fabbed for myself. Any new observations or suggestion for the component (re-)assembly process?

Thanks! I will definitely look into this once I have some time for a new project.

Which diodes are you having problems with? FWIW, I replaced the infamous DL21 and DL22 Zeners with Onsemi's 1N5931BRLG years ago, and they've been running well since.

Good point, I was kind of assuming that @ArjenCNX wanted to do it in VGA mode only, but it would be great if it could be universal.

Are you looking for an easy way to switch the line sensing and B+ back and forth with switches, or simply a way that doesn't require cutting and bodging to do VGA mode (like with zero-ohm resistors that can be populated in the appropriate positions)?

Seems very doable with a VGA-to-HDMI converter, which you can probably find in IC form. The main challenge would be dealing with the CC’s composite sync, as it doesn’t natively produce independent VSYNC and HSYNC signals, like standard VGA. I use the LM1881 on my board to pull out VSYNC, and...

Sounds great. If you might consider socketing your XC1186B on this particular board, then you could swap in mine for initial testing. I’d be happy to send one to you, but it might take a little time (I only have one v3 board with a lot of rework). I’m trying to finish up v4 changes, and I’m...

Congrats! That's great!

It's been a long time since I last looked at that zener, but I believe it is indeed a 36V part. My indication of of x-ray detection on the associated input on the XC1186B is mostly by supposition, since I observed that it will indeed kill the horizontal deflection if an injected voltage on the...

Sounds almost like it's in high-res mod mode, but I assume that's not really the case. :) Have you looked at pot PP1? I don't think you can actually adjust the nominal B+ all the way up to 80V with PP1 alone, but it might be worth a look.

https://github.com/jonschultz

I've often wondered if it would be a worthwhile project to try to adapt a more commonly available flyback to work with the Color Classic. I think it's definitely possible, but would likely require additional voltage regulators for the various odd semi-high voltages required by the analog board...

I had pretty good success with an LC575 flyback in a Color Classic, though I found that the 86V B+ version of the VGA mod was necessary to get an adequate horizontal raster. I think I also probably had to adjust the G2 voltage and the RGB background pots relative to their optimal positions using...