12-08-2018, 09:09 PM
I suspected that low EHT voltage is the cause of poor focus, today I measured it and found it to be only around 3kv dropping to around 2800 volts at full (but still dim) brightness.
I have already tried removing the EHT capacator and regulator stic but it makes no difference to the picture. I have also bought a new PL81 line outut valve but that made no difference either.
To measure the voltage I used a string of 10 M ohm resistors feeding into my test meter. I got similar voltage readings on my AVO using its 3000 volt range.
I'm not sure what the EHT should be, Ive seen 9kV mentioned.
David
I have already tried removing the EHT capacator and regulator stic but it makes no difference to the picture. I have also bought a new PL81 line outut valve but that made no difference either.
To measure the voltage I used a string of 10 M ohm resistors feeding into my test meter. I got similar voltage readings on my AVO using its 3000 volt range.
I'm not sure what the EHT should be, Ive seen 9kV mentioned.
David
