Make your own toobs!

not many do. I've seen homemade tubes of all types & CRTs too

NT

Yes, they do...the fellow here is extremely talented...even produced curves for his tubes.

I lived not very far from the Sylvania tube factory in Pennsylvania. Quite a few articles on the net about it and the physics and metallurgy that wen t into designing and fabricating high quality electron tubes. It was gener ally acknowledged that Sylvania tubes equaled or surpassed RCA tubes in qua lity and long-life.

In a wild day dream one week I did quite a bit of searching of what it woul d take to create a high quality tube factory equal to what sylvania had. T o actually put the equipment in place and the associated know how. It seem ed to me that a lot of the 'art' (craftsmanship) has been lost and would ne ed to be relearned, thus making a business endeavor extremely risky. It als o seemed that some of the underlying physics/chemistry/metallurgy would hav e to be rediscovered. That put it out of my scope of knowledge.

I can see an ad in IEEE spectrum: Wanted - electronics engineer/physicist e xperienced in electronic vacuum tube design and fabrication. Don't think I 'd get many takers. Looks like will have to subsist on Russian and Chinese 'knock-offs'... Well, it was a nice dream...

es for his tubes.

te a few articles on the net about it and the physics and metallurgy that w ent into designing and fabricating high quality electron tubes. It was gen erally acknowledged that Sylvania tubes equaled or surpassed RCA tubes in q uality and long-life.

uld take to create a high quality tube factory equal to what sylvania had. To actually put the equipment in place and the associated know how. It se emed to me that a lot of the 'art' (craftsmanship) has been lost and would need to be relearned, thus making a business endeavor extremely risky. It a lso seemed that some of the underlying physics/chemistry/metallurgy would h ave to be rediscovered. That put it out of my scope of knowledge.

experienced in electronic vacuum tube design and fabrication. Don't think I'd get many takers.

** In the late 1970s when the Sylvania tube factory closed, the manufacturi ng equipment was offered at auction and the purchaser was Hartley Peavey of the Peavey Electronics Corporation - maker of thousands of tube guitar amp s.

His idea was to manufacture runs of tubes commonly used in audio amplifiers and sell them under his brand to other amp makers and the public.

Then the Soviet Union collapsed, as predicted by Ronald Reagan, making Russ ian tubes available to the rest of the world at prices lower than the cost of p roduction in the USA. Many of these were near identical to popular RCA and GE types or were easily enough adapted to match them in term of pin out et c.

The Chinese had already bought up machinery from Europe and were making sim ilar tubes of very ordinary quality at low prices too.

AFAIK the Sylvania machinery is sitting in storage somewhere in the US.

The Russians had always been making tubes of good quality for home and mili tary consumption so the engineering knowledge was in place while the Chines e OTOH had a bit of learning to do.

.... Phil

I have an number of Raytheon-branded tubes e.g. 6201, an industrial

12AT7, and another numerical-tube starting with 6, some 12Axx-type for computer use that I'm blanking on the number of.

Do you know if Raytheon produced these in-house or were they second-sourced?

Check the EIA Code:

Sceptre

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