Keithley Model 240a HV PSU

[@PapasDino]

Nice unit Simon...I just acquired a HP334A Distortion Analyzer that a bit of disassembly and a generous application of DeOxit to all the switch wafers brought back to life; "tuner cleaner", greatest thing since sliced bread! Thanks for sharing!

[@ovalwingnut]

Very interesting 25mins. Super to be exposed to such unique equipment. I love the "classics". Clunky knobs rule. Beats LCD's and membrain buttons, or worse. I see no reason that this unit can't serve future generations. In that respect we are all tasked with passing it forward. Thanks so much. Cheers

[@danishnative9555]

Good fix Simon. Wonder what GE regulator valve was used? I once had a bunch of those "Bumblebee" paper wax caps in my parts collection, but discarded all of them when I tested before using to repair another vintage device. The unsuspecting guitar purists foolishly pay big bucks for them on Evil Bay. There is nothing special about them. Can't say about "Black Cats" I think most were made by Sprague.

[@xDevscom_EE]

Nice bit of Keithley gear. But I would clean that electrolyte residue on PCB from old caps!

[@SoddingaboutSi]

There wasn't any was there?

[@Andrewausfa]

Make a nice capacitor reformer as well if you're that way inclined.

[@SoddingaboutSi]

It would Andy. And current limited too so no explosive surprises!

[@allthegearnoidea6752]

Ooh quite envious looks amazing quality very nice find. I have a 500 volt power supply, uses something ridiculous like 10 power pentode output valves.

[@amirb715]

this is a bit out off topic but where did you get those nice LCR meter alligator clips?

[@SoddingaboutSi]

Ebay. A Chinese seller. Type in Kelvin clips.

[@materialsguy2002]

Had a good chuckle when you said transported by “herpes” . Thank for the video. You appear to have a hardcopy manual for your 240, is there anything on the 245 (2kV model) in your documentation?

[@SoddingaboutSi]

No Sorry. Didn't know they even made a 2KV version! Thanks for your comment.

[@materialsguy2002]

Simon Spiers : No worries. In fact I did a bit more digging and found that there were several other models in this series: 245 (2.1 kV) and 246 (3.1 kV). It turns out that the 245 and 246 are very similar in construction, and circuit design AND the 246 manual is readily available.

[@thulinp]

Note that .033 MFD is NOT 330nF

[@SoddingaboutSi]

THat was a catch to see if you were awake! No your right well spotted!

[@TheDefpom]

I think I saw that unit on eBay, I almost bought it!

[@ydonl]

With 0.02% stability, and 0.005% load regulation, I think the comments about this being "just a power supply" and "will drift anyway" are a bit out of place! :) I would call it "wow."

[@Chriva]

That model name is so misleading :D I read it as 240 A(mps) and wondered where the hell you found a beast like that

[@jonathanhendry9759]

In retrospect "240A" might not have been the best model number for a high voltage power supply.

[@TheDefpom]

Oo looks interesting