Hi all,
So last year my venerable old 2465A developed a weird intermittent fault. After some time - arbitrary and not temperature related - this fault would arise whereby the screen would become *really* bright with some spurious artifacts showing up as well. When this happens, the screen brightness control fails to have any effect and I cannot turn that dazzling brightness down.
Now, from what I've read, I need to monitor TP73's voltage ('grid no. 1' to the CRT) and see if it changes when the fault arises. So I've stripped the casing away and removed the HV safety/warning shield from the HV supply board A9 and attached a scope probe to TP73. The service manual provides a diagram of how the waveform on TP73 should look so I'm all revved-up waiting for the fault to materialize (which it invariably does when I try to use it to check anything). Guess what? I've had the damn thing on now for 5 hours and it's not missed a beat! Behaving perfectly normally with no sign of any screen issue at all. Bloody intermediate faults. I hate 'em!!
Jinxie
Jinxie