As the title says, I've got a failed "test 3" on my HP 3456A meter. I went through the manual to do the pinpoint tests, and it seems to be "T1" on the A3 board. According to the manual, this is HP p/n 9100-2616, Transformer - Pulse bifilar wound, 18.0 mm, coce 28480.
link to manual:
https://www.sonoma.edu/esee/manuals/03456-90006.pdfTroubleshooting steps I'm following start on pg 310, paragraph 8-A-37. The pinpoint test for the transformer is 8-A-41 on the next page.
Some questions about this:
As a sanity check, is there any other means I can verify this? The diagnostic process has me check for a particular waveform "at the core of A3T1". I touched the probe to the ferrite core, and got no waveform. I did get the waveform specified at the pins of U19. Is this the proper means of testing the transformer?
Is this a part I can substitute, or am I looking for a very specific and probably grossly obsolete HP part or complete A3 board as a parts donor? Any chance i could just re-wind this? Looks like two pieces of magnet wire, nothing overly special.
Lastly, is it probably something totally unrelated to this part and I'm chasing my tail? This is an all-original 1982 vintage unit. All the caps look visually OK, no leakage or bulging but I have not tested or replaced any of them.
I appreciate any insight you fine folks might offer.