Re: IBM PS/1 Monitor (CRT)

can the tube be damaged during arching?

Re: IBM PS/1 Monitor (CRT)

This is the best I can get, the 60% grey seems to get a bit better over time, when i turn on the monitor it's inexistent
1. 100% contrast / 50% brightness
2. 100% contrast / 100% brightness
3. 75% contrast / 100% brightness
4. 50% contrast / 100% brightness...

Re: IBM PS/1 Monitor (CRT)

could it be that the RGB IC is bad? I have three more I could replace it.

Re: IBM PS/1 Monitor (CRT)



You mean the one on the flyback?
that seems to work fine, my problem is the contrast for example in DOS the text should be bright white but it's faded and yellowish if I turn up the brightness the text will get brighter but also the background


I also added a picture with the board code...

Re: IBM PS/1 Monitor (CRT)

After arching, I tried covering the hole in the flyback and it worked for a few hours and the pictures was as the first picture.
The screen doesn't go dark if i turn the brightness down and the contrast control does have an effect on the picture but after I turn it like a quarter down the image disappears, the voltage on the pin 12 is between 7V and 4V when i turn the brightness....

Re: IBM PS/1 Monitor (CRT)

I don't have schematic I've attached a photo with some labels
If the pwoer supply had a problem shoudn't be a problem with brightness also? the brightness seems to work fine.
As you can see in the photos the flyback transformer is the same model.
I've checked some diodes especially around the flyback transformer and the neck board.
I'm going to reflow the neck board solder just in case but i doubt thats the problem.

I've played with the marked potentiometer and the contast got better but i've set it to max (or...

Re: IBM PS/1 Monitor (CRT)

Looks like when i lower the resistance of that adjustable resistor the maximum contrast improves but still not enough could it be one of the caps? or both?...

Hello, I have an IBM PS/1 SVGA CRT monitor, it was working ok untill it started to make a disturbing noise and the image was as if it was turning off constantly,
I opened it and i found that the flyback transformer was discharging to ground, I've tried isolating the leak, no success, I've replaced the transformer with exact replacement, it turned on fine but now i have extremely washed out picture see IBM_21.jpg, after that I replaced the RGB amplifier and the image got a little better with colors but almost no contrast see IBM_22.jpg

I've checked diodes around flyback transformer,...

Re: New Members - please post your introductions here

Hello, I have a retro IBM CRT monitor that needs saving.