There has been a lot to do at the office the last months so I haven’t had much time to spend with my projects in the workshop…
This weekend I have been repairing a Hantarex Polo monitor from an OK baby cabinet. It had its CRT panel damaged in a transport and somebody else replaced it by a new one but couldn’t get the monitor to work, it just gave a ticking sound when started. After some investigation and surfing for documentation I found out that the monitor was a Polo/2 and the new CRT panel was from a Polo. Electrical they are identical but the connections are marked different between the two and in this case two cables were mixed up causing the 25 V from the PSU to be shorted to ground. After correcting the connections the ticking disappeared and I had glow in the CRT, but no EHT. After some more investigation I found out the deflection yoke was connected to the video input connector instead of to the proper yoke connector. When the yoke connector isn’t connected where it should be there are no power to the LOT driver transformer and no EHT. When connecting the yoke to the proper plug the monitor worked again.
I don’t know how the CRT panel could get so damaged without also damaging the neck of the tube?
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