21-05-2015, 11:51 AM
Magic Mark. You have been christened!
R137, 68k histab 1% is O/C.
R152 220k is 248k, ok.
R137 changed for 67.5k
Now have 5.6v across R136, +6.3v on TR82 base. ( voltages all rel to 0v rail i.e. C407 neg )
Now R405 is running hot after 2-3 mins. Random tick from what I assume is eht box buried in the middle of the steelwork.
BUT- progress-- Horiz shift coarse or fine moves dots 1cm left in 1st 20 degrees of travel. Beam locate does the same.
Shift control to move channel 2 dot up, it goes diagonally to top right of screen, taking channel 1 dot horizontally with it.
Focus seems to have deteriorated, dots are larger but control still has some effect.
Single shot lamp is lit constantly, reset does nothing.
I assume that the 180v supply is overloaded as R405 is running hot. As the volts on TR82 now seem to be OK, perhaps the overload is on the the supply to the Y amps. If I could find the connection, 111/57, I would dis it and see.
Your detective work is brilliant, wish I was this good with these cold valve thingies. Thanks, any further ideas welcomed if you have the time and patience.
Sam.
R137, 68k histab 1% is O/C.
R152 220k is 248k, ok.
R137 changed for 67.5k
Now have 5.6v across R136, +6.3v on TR82 base. ( voltages all rel to 0v rail i.e. C407 neg )
Now R405 is running hot after 2-3 mins. Random tick from what I assume is eht box buried in the middle of the steelwork.
BUT- progress-- Horiz shift coarse or fine moves dots 1cm left in 1st 20 degrees of travel. Beam locate does the same.
Shift control to move channel 2 dot up, it goes diagonally to top right of screen, taking channel 1 dot horizontally with it.
Focus seems to have deteriorated, dots are larger but control still has some effect.
Single shot lamp is lit constantly, reset does nothing.
I assume that the 180v supply is overloaded as R405 is running hot. As the volts on TR82 now seem to be OK, perhaps the overload is on the the supply to the Y amps. If I could find the connection, 111/57, I would dis it and see.
Your detective work is brilliant, wish I was this good with these cold valve thingies. Thanks, any further ideas welcomed if you have the time and patience.
Sam.
Boater Sam.
