Hello
My 54600B oscilloscope stopped triggering. The problem seems to be that for some reason U73 (SPT9687 video comparator) LE-input (pin 4) keeps the comparator in latched mode (Pin 4 voltage ~ -88mV and TRHYS ~ +0.36V) disabling triggering. However - I do not know why this happens. Does anybody have the circuit diagram for the trigger circuitry and/or component placement picture. All help is greatly appreciated.
BR, Jacko (oh8nj).
My 54600B oscilloscope stopped triggering. The problem seems to be that for some reason U73 (SPT9687 video comparator) LE-input (pin 4) keeps the comparator in latched mode (Pin 4 voltage ~ -88mV and TRHYS ~ +0.36V) disabling triggering. However - I do not know why this happens. Does anybody have the circuit diagram for the trigger circuitry and/or component placement picture. All help is greatly appreciated.
BR, Jacko (oh8nj).
There is a CLIP link there, and the sch is probably close enough for you to figure it out.