HP CRO Knobs Needed - Page 1
Forum section: electronics / general

author: Technomaniac
author_rank: Contributor
timestamp: September 15, 2020, 11:40:32 pm
content: Hi All. Some time ago I posted this on the forum:WTB LFS Hi all. I've been off-grid for a few years, and when offered an HP 1707B Oscilloscope for $50 AU, especially as it has an alternative 24v input which is isolated from the ground of the CRO, I jumped at the chance. I fitted a cable and plug which would mate with my 24v installation, and put the instrument aside until I needed it recently. When I removed it from the shelves, I was shocked to see the state of some of the front panel knobs. Split, warped beyond patching up.(We've had some VERY HOT SUMMERS!) I'm looking for those below:Channel A and B Volts/Division MP10 part no. 0370-0966 (2 needed)DISPLAY (alt-chop-A+B-B-A MP12 part no. 0370-2046TIME/Div (Coarse only with transparent thumb-lug and transparent indicator disc) MP21HP part no. 01701-67414Delayed Sweep-Mixed Sweep-Main Sweep MP8 part no. 0370-2452Div-Cal (Little Knob in front of above) MP9 part no. 0370-0962Focus Knob MP7 part no. 0370-1005Some have printing which would be difficult to copy if I have to mould new ones. And I don't really want replacements which also have cracks and warps! This might mean that they have to come from a cooler climate?I'm still looking for the knobs, they're so badly split that I can't use the CRO. Other models don't seem to use the same ones. I'm pretty handy making things and fairly well equipped with lathes and milling machines, so might be able to make some metal ones but what an enormous task! Engraving the numbers would be near to impossible.Has anyone written off one of these which still has good knobs, or found a stash of new knobs anywhere?

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: September 21, 2020, 06:54:49 am
content: I have a Tek 2235 which had a few cracked knobs, luckily most were simple enough to 3D print a replacement forMaybe you could do the same?

author: Technomaniac
author_rank: Contributor
timestamp: September 24, 2020, 12:02:24 am
content: Thanks. I bought a 3D printer week by week from the newsagent in kit form. Got halfway through the construction and found something I didn't like and would choose to modify. Haven't gotten back to the project. Time I DID ! I wouldn't know how to print from a scan or a photo though, can you suggest any good literature on that subject?

author: Stray Electron
author_rank: Super Contributor
timestamp: September 24, 2020, 06:55:02 pm
content: Can you post a picture of the knobs that you need or link to an online picture that shows them? I have a couple of old HP scopes for parts. I think they're 1727s so the knobs might be different.

author: Technomaniac
author_rank: Contributor
timestamp: September 24, 2020, 11:05:15 pm
content: Channel A and B Volts/Division MP10 part no. 0370-0966 (2 needed)DISPLAY (alt-chop-A+B-B-A MP12 part no. 0370-2046TIME/Div (Coarse only with transparent thumb-lug and transparent indicator disc) MP21HP part no. 01701-67414Delayed Sweep-Mixed Sweep-Main Sweep MP8 part no. 0370-2452Div-Cal (Little Knob in front of above) MP9 part no. 0370-0962Focus Knob MP7 part no. 0370-1005The attached photo is from the Owners Manual, the scan turned out better than my photos, as I don't presently have good closeups. I think the knobs were used on that model ONLY, I have downloaded manuals from other models and compared part numbers.Cheers!

author: psykok
author_rank: Frequent Contributor
timestamp: September 25, 2020, 01:32:48 pm
content: Hi,I just salvage a HP 17xx Scope and have a lot of parts available.I will check what I have for remaining knobs.Alex

author: dzseki
author_rank: Frequent Contributor
timestamp: September 25, 2020, 02:31:34 pm
content: Quote from: psykok on September 25, 2020, 01:32:48 pm17xx, which exactly? The faimly is big and parts compatibility vary widely.

author: ANTALIFE
author_rank: Frequent Contributor
timestamp: September 28, 2020, 12:15:37 am
content: Quote from: Technomaniac on September 24, 2020, 12:02:24 amNo worries! I think the easiest thing to do is take some measurements with calipers and start keying the info into what ever MCAD program you are familiar with. If you don't have a preference then try OnShape, this is online based and should work just fine for making up some knobsAlso be prepared to print a few prototypes as you get the dimensions just right