My oscilloscope, an old Gould Advance OS3000 has developed a fault that manifests as a loss of trace/dead screen.
I was working on a basic circuit and on turning a dial I lost the trace. The scope is triggering but nothing will bring the trace back, on either channel, in auto, normal or free run.
At the moment the screen is super dim. There is no change to the brightness when I switch on and off. I think the glow I am getting is just the reactance to ambient light before I switch the light off.
There is a glow at the rear of the CRT.
I've injected -12v to the rear Z port and I get no dot. Said something about this in a tek document I found.
I've probed the +/-15v and the +150v on some of the PCBs and they are close to nominal.
Before I tear this thing down and look for blown stuff is there any particular area I should be looking at. Bear in mind I know very little about how these scopes work internally, although I do know to treat the high voltages with respect.
Many thanks for your help.
I was working on a basic circuit and on turning a dial I lost the trace. The scope is triggering but nothing will bring the trace back, on either channel, in auto, normal or free run.
At the moment the screen is super dim. There is no change to the brightness when I switch on and off. I think the glow I am getting is just the reactance to ambient light before I switch the light off.
There is a glow at the rear of the CRT.
I've injected -12v to the rear Z port and I get no dot. Said something about this in a tek document I found.
I've probed the +/-15v and the +150v on some of the PCBs and they are close to nominal.
Before I tear this thing down and look for blown stuff is there any particular area I should be looking at. Bear in mind I know very little about how these scopes work internally, although I do know to treat the high voltages with respect.
Many thanks for your help.