AnsweredAssumed Answered

HP8753A focus problem

Question asked by Harke on Feb 9, 2008
Latest reply on Mar 8, 2008 by Harke
Dear group,

I have a HP8753A with an unfocused display. I think the tube itself is not quite dim, a bit maybe, but still very usable. I do not think of a complete replacement, yet, if feasible.
The text is just readible. Brightness and focus controls work, but apparently not enough. I checked supply voltages but found no real deviations. I do not have a service manual, just checked against internal available info on pcb's etc. I also tried some internal pots carefully but without succes. Removing the processor board gives the proper test pattern, but, obviously, also out of focus. I did not check EHV.
I welcome any advice.
Thanks in anticipation,

Harke, PA0HRK
PS: I tried to remove the display unit. Do I need to remove the frontpanel completely or can the brown bezel be taken away?  

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