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Comment by kens | Hacker News Reader

Yes, the whole AGC works; this article discusses the power supplies in particular. The video playlist is at: https://www.youtube.com/playlist?list=PL-_93BVApb59FWrLZfdli...

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Were you able to see who made the tantalum capacitors? Or did the cordwood construction prevent that?

I ask because my dad was Group Product Manager at Kemet during this time period. Growing up, he mentioned their products going into several aerospace systems (various ICBMs and military projects, etc) as well as the IBM System 360. But he never mentioned involvement with Apollo and I'm curious if he might have had a hand in the AGC.

BTW, your link to the NASA contract drawing is incorrect - here's the one you probably wanted.

http://www.ibiblio.org/apollo/SCDs/scd_1006755t.pdf

It would almost certainly have been Kemet, as they really made their reputation on those wet-slug hermetic tantalum caps. If you take apart a piece of HP gear from the 1960s-1970s timeframe, you find that those are the ones that are still good even today.

I definitely remember seeing Kemet markings on at least one of the caps in the power supply restoration videos.

I recall him saying they sold to Tektronix as well as HP.

The story he told me was that when the DoD wanted to buy scopes from Tek, rather than jumping through all the acquisition process hoops, Tek just handed them a glossy product catalog and told them to pick out which ones they wanted. Which went about as well as you might think, but back then there really was no substitute for a Tek scope so the Pentagon caved.

Yeah, I'm going through the same process right now with a similar product and DoD customer. What happens these days is that they send out an RFQ to half a dozen different "approved suppliers," which is government-speak for "People who have jumped through the necessary hoops to drop-ship stuff to the Federal government from the basement in their house."

Whichever "supplier" marks up the product the least -- a product they will never see, much less stock -- will presumably be the one who wins the right to pass along the order to me. This is the government's idea of competitive bidding.

It's just nuts. The waste, overhead, red tape, and opportunities for corruption are just totally batshit nuts. But what can you do...

> but back then there really was no substitute for a Tek scope so the Pentagon caved.

Well, they still got their own SKUs with (minor) modifications.

Such as being cloned shamelessly (and illegally) by Hickok, IIRC.

That was with the 500 series, Tektronix supplied 5000 and 7000 series systems to the DoD, e.g. as the AN/USM 281.

The (corrected) drawing says Sprague made these capacitors: http://www.ibiblio.org/apollo/SCDs/scd_1006755-.pdf (I don't know if Kemet made other capacitors used in Apollo.)

That's a bummer, but thanks for taking a look. Sprague was and still is a competitor to Kemet.

To the contrary! In our AGC, all of the capacitors not tucked into cordwood holes sport a KEMET logo and part number: https://photos.app.goo.gl/oGsrgXBpNMccmkWV7

I think the Computer History Museum's might have Sprague caps in it, though.

Yep, that's the capacitor I was referring to below. At least some of them were definitely Kemet parts. I don't remember seeing any Sprague logos but I imagine there were some of those around, too.

I checked and there's a visible capacitor in the AGC's power supply with the Kemet name on it. So maybe your dad had a part in the AGC. Here's a photo by Mike Stewart showing the Kemet capacitor: https://photos.app.goo.gl/iWcWNqt1UzUzyeAz9

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