Wavy TRS-80 Model 1 Display

[wheagy]

My model 1 display is wavy (see video). It gets progressively worse as I use it. After about an hour it gets pretty bad and is worse than shown in the video. I’m a bit nervous working around CRTs so wanted to see if anyone knows what might be causing this, too minimize my time messing around in there? I realize it could also be something in the M1 video circuitry in the keyboard/CPU.

Thanks,

Win

https://youtu.be/8kmM392wZLM

 

[LambdaMikel]

I’m a bit nervous working around CRTs so wanted to see if anyone knows what might be causing this, too minimize my time messing around in there? I realize it could also be something in the M1 video circuitry in the keyboard/CPU.
https://youtu.be/8kmM392wZLM

Understandable - same here... even though I know how to discharge the tube with a screwdriver etc. (YouTube videos out there).

Have you tried connecting another monitor to double check if the fault is in the M1?

 

[wheagy]

Finally was able to get back to this today. I forgot, but asking if I had a second monitor jogged my memory. I do and I tried it (temporarily set it on a chair and plugged it in - this will be important in a minute). It was a pretty good picture...stable. I was happy to see this so swapped it out. Booted with this monitor and same issue - wavy display picture. Lifted it up about a foot and the display stabilized. Checked a few things, but long story short, no issue with the TRS-80. Turns out I have an Amiga next to it and the Amiga monitor was causing it. I didn't even notice the Amiga monitor was on. Ugh. Without swapping it would have taken quite a bit longer to notice what was happening, so thanks for the suggestion.

Win

 

[rittwage]

Oh wow... sometimes the easiest things get us! At least you didn't start pulling the monitor apart and replacing parts.

I have had this happen when I had an old cell phone out of my pocket and on the desk near a monitor. In the old days at least, that used to cause weird effects on CRTs.