Caveat : CRT Monitors contain lethal voltages, even when disconnected from power, do not attempt to open or repair any CRT.
Quite a few years ago now I bought a 9" Sony PVM which I use on my repair bench. Just in the last half a year it has been playing up and after a few minutes of being on, loses all colour.
On the Internet I found two resources that were very useful to me.
The excellent video from RGB Bob and also this video from Retro Tech.
Initially I replaced the orange variable capacitors on the board as per RGB Bobs video, the parts are CV101 and CV102.
You can see the markings better once they are out. Be sure to take note of the FLAT side, this will correspond to the components shape when you put it in.
The replacement also includes some bypass capacitors as well. Solder in the new variable capacitors first and then put the bypass capacitors on the the back. Please see RGB Bobs video for details and the replacement parts list.
Once they were in I was lost. When I turned the monitor on it was still back and white. I used a small flat head screw driver to adjust the capacitors but couldn't get the colour to return. I made sure I set each capacitor back to the original starting positions each time.
So I had a look at the main IC on the board and the soldering was a little average on the pins. So I decided to re-flow and refresh the solder there.
After that was complete it was still back and white. So I went back to the Capacitors and tried again, this time turning them very slowly around an then back to the original starting positions.
No luck on CV101, so I put it back to it's original position.On CV102 I got a small blip on the screen, not colour but a flickering
of the image. I VERY VERY slowly turned the capacitor back over where
the blip occurred and the screen suddenly displayed full colour in all of it's glory!
So the lesson here is, if you have to tune it back in, be very very patient and watch the screen like a hawk for minuscule changes.
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