Products > Test Equipment
HP 1741A oscilloscope - restoration project
MuchMore:
Ok I guess that I am not willing to spend 1/8 the money I paid for the scope on an cap the may fail in the future... and when it fails I will replace it with a good cap that will do the Job.
@lowimpedance I can't find an power-resistor on the vertical-amp?? which one do you mean??
The high voltage supply look not sooo good, can someone take a look and tell if there is a part that may be at the end of its lifetime??
lowimpedance:
That would be R3 on PCB A5 (see circuit diagram) fed from 43V rail. (HP1740)
The High voltage PCB has a little 'soot' on it which is normal for circuits running at high tension (Old CRT TV's for example), so nothing from your photo's looks too bad actually.
Maybe a gentle wipe with a soft cloth (and a little IPA) to remove the soot.
Check the soldering for any suspect joints, one last inspection and put the cover back on , and don't worry about component failure until it does!!.
Clean your vertical attenuators.
tggzzz:
I've recently restored a 1740 that was more-or-less functional before I bought it; it now works well. Nice machine.
The remaining "suboptimality" is that the digits on the timebase knob/dial are hardly visible, partly due to grime on the transparent plastic, partly because the charaters are worn away. I'd like to clean the transparent plastic and replace the legend. How do I mechanically disassemble the knob/dial itself, so that I can access the legend?
(To state the bleedin' obvious, I can get the dial out of the machine).
Thanks.
tautech:
A 1740 manual should be available from one of the links in the first thread in the Repair board.
HP used retaining screws that require very fine hex keys to remove the control knobs, you will need the correct sizes. (imperial)
Search other restoration threads as some senior members have unbelievable skills and tricks to do exactly what you need.
I've also got a 1740 for a wet day project, had another a few years back before I got into DSO's.
tggzzz:
--- Quote from: tautech on August 29, 2014, 11:27:18 pm ---A 1740 manual should be available from one of the links in the first thread in the Repair board.
HP used retaining screws that require very fine hex keys to remove the control knobs, you will need the correct sizes. (imperial)
Search other restoration threads as some senior members have unbelievable skills and tricks to do exactly what you need.
--- End quote ---
It came with the repair manual, I'm pleased to say, but it is silent on disassembling the knob.
I had a quick look a while ago, and couldn't be sure it was a hex screw; I wondered whether it was a foobar, where "foobar" is effectively an expanding coiled spring shaped like a very thick danish pastry :). Now, if only I could remember the real name for a "foobar".
Either way, I'll have another look, and thanks for your reply.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version