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This gem, almost unobtanium, was designed to be a low-cost oscilloscope CRT and appeared in the RCA 151 oscilloscope.

This one is probably one of the earlier units, but RCA didn't always date code things in a way you could decipher. It's packed in the original box (disintegrating) with the original paper pack material. This is a spare for my 151 scope, and goes with the 885 (in the background) posted earlier.

This, along with the image multiplier I posted a week or so ago, is one of the more unusual tubes in my parts cabinet.

(This post is for that special someone on Poal, you know who you are.)

This gem, almost unobtanium, was designed to be a low-cost oscilloscope CRT and appeared in the RCA 151 oscilloscope. This one is probably one of the earlier units, but RCA didn't always date code things in a way you could decipher. It's packed in the original box (disintegrating) with the original paper pack material. This is a spare for my 151 scope, and goes with the 885 (in the background) posted earlier. This, along with the image multiplier I posted a week or so ago, is one of the more unusual tubes in my parts cabinet. (This post is for that special someone on Poal, you know who you are.)

(post is archived)

Beauty, joy forever! I'd buy a pallet full! Although, I doubt I'd want to "play" around with 610vdc though, not without some serious clamping going on in the power supply if there's even a hint of a problem...

Datasheet: https://www.labguysworld.com/CRT_913.pdf (labguysworld.com)

Couldn't imagine only really being able to take qualitative measurements with these things... suppose it's a great help to know the shape of your signal even if you can't quantify it so well...

Most of the RCA 151 stuff I've found refers to it as "oscillograph." Time to go read about what the difference is between o-graph and o-scope... after work.

Thanks for the post!

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Oscillograph is just the "old" term for Oscilloscope, much like pF used to be micro-micro farads and Hz used to be written as "cps."

I do have a RCA 151, I'll get it out this week and do some pictures. And you're right, it was for showing the shape of the waveform more than actual measurements. Those instruments cost a lot more, this tube put a scope in the range of the small shop.

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There are other 1" CRTs out there, the most common being the 1CP1 made in the 50s. There were literally tons of these made for military and other use, you may be able to pick up a few of those for under $50.

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So RCA was pushing critical race theory back in the 30s? Boycott RCA!

But seriously, that is an awesome thing to have in your collection. I can't get a proper sense of scale on this CRT, but it does appear to be under 2" in diameter. That's one tiny scope screen! Do you know if this CRT is electromagnetically deflected with a yoke or electrostatically deflected with internal field grids? I imagine it was designed for low bandwidth applications where the use of yoke deflection would not be a significant drawback so I could see this helping keep the cost down. I should do some searching for info on this CRT since I have so many questions I would like answers to. That really is a cool little tube you got there.

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It's electrostatically deflected. It was designed to be a cost-reduced tube for scopes back in the 30s.

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Very unique.

This would be worth reposting when the site goes to new server since this won't make the transition.

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I will probably package all of the last few posts up into one larger post with a demo of the device.

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So can you technically see into other dimensions?

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Only on the floor models.

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Can you measure brainwashing signals like the x files?

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Not on this one. I have another device in the office for that. It may look like a Racal-Dana 6000 rack-mount integrating multimeter, but I assure you - the firmware in this one is quite special.

Sooooo what.

Lol

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I didn't expect you to appreciate the device or it's place in the history of electronics, so it wasn't posted for you. But you can't resist commenting, can you?

♥♥♥ XOXO ♥♥♥

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How dare you share old technology in the old technology forum. The fuk man..

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My friend got mad because I told him that low power RF wasn’t the supreme danger he claimed.

boooring

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You commenting is like Pringles. Once you pop, you can't stop.

♥♥♥ SWAK ♥♥♥