I haven't been able to find this specific issue on AtariAge, Youtube or through Google. Maybe if I knew the correct term to describe the issue I'd find ten thousand solutions, so I'm a little nervous mentioning my issue here.
Here's the short version: I have a heavy sixer that consistently outputs video in black and white with many well spaced vertical lines evenly spaced throughout the image. It looks like this:
Excuse the blurriness of the image, that's my shaky hand. The image on screen is actually quite crisp. Note that this is with the color mode selected, but the display appears in black and white with vertical lines throughout. The signal itself appears to be quite strong, it's not too fuzzy and doesn't have much of any interference.
The getting longer version:
The above image is in 'color', the actual black and white mode looks to be what you'd expect:
I spent a week working on the issue, I cleaned all the slot and cartridge contacts, replaced one then the other 22uF Capacitor, I replaced the 2200uF Capacitor, then I replaced the 5v regulator. Using a multimeter I took a few samples and the numbers are in the range that I expect.
All this time I was using a Coaxial F Plug to go to the TV. Then I thought back to a long time ago when I remembered the system actually outputting color and (guessed) that maybe I was using the original RF switch. So I tried that, and guess what happened? Color.
So I thought to myself, I didn't know a F Plug would have this effect, but I'm so happy it's working I'll call it a week and put the system back together and consider myself lucky.
But once I put the system all back together and tested it one more time with the RF Switch? Back to Black and White with vertical lines. And let me tell you, in the week I was working to fix the problem I must have tried the system 30 times, five different games on two TVs (An HDTV is pictured, the other is a 1990s Trinitron). Every time was black and white with vertical lines. It seems like so much of a coincidence that as soon as I tried it with the RF Switch everything worked great, but alas it was only one time.
At this point, I'd be happy just to hear someone else say they've seen this issue before. As I said before my esteem is already low because my searches have been fruitless. The video cable looks in great shape from the box all the way to the tip. Games work immediately when I turn the system power on every time. Are there more places I should check the voltage? Any other suggestions?