212D

[Chris P.]

Can anyone tell me about a 212D triode? I tried doing a google search but didn't come up with much info.

[Bill, KD0HG]

Western Electric?

[W2XR]

Can anyone tell me about a 212D triode? I tried doing a google search but didn't come up with much info.

Chris,

Try looking up 212E. That is a WE tube. I am personally not familiar with the number 212D, and it is not listed in my WE tube manual.

The 212E is a very collectible high power audio triode the Asian homebrew audiomaniacs go nuts over, particularly when used in a single-ended class A topology with zero NFB. It is rated at 275 watts plate dissipation and a maximum Ep of 3000 volts. It was used in several WE AM broadcast rigs, and may used in either class A, class B or Class C service. A very versatile tube, indeed.

73,

Bruce

[Chris P.]

Thanks

212E turned up a little more info.

Here is a pic off my site. It is a Sylvania. Looks like it would make a nice heater. Specs say 250 watts in plate modulated service. Hmmm I'm getting ideas.

[W2PFY]

It could be worth a rather nice sum on epay. I had one with a Bakelite base but I think mine was a 211E. Some guy in Korea bought it to build an audio amp out of it.

I didn't think the one I had would be worth building a transmitter around. I think the Asians like the metal plate type tubes. Trying to buy a back up 211 is not affordable and I'll bet it the same with the 212.

[KE6DF]

I like these funky old tubes.

Here is an ad I found googling.

Can't get it to upload. Too big.

I emailed it instead.

Dave

[KE6DF]

And here you can buy on epay (and I do mean pay) a spare for a mere $2495.

http://cgi.ebay.com/Western-Electric-212-D-Vacuum-Tube-Very-Rare_W0QQitemZ170421520680QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item27adea0928

[W7TFO]

The 212 had an RF counterpart, the 308A.  Looked the same, but with the plate out the top.

Western Electric designs had moved on by WW2 to the 357A/B as used in the 443 1Kw AM transmitter.

None of these tubes are cheap or plentiful today, and Machlett Labs took over production of them in the early 50's.  Machlett tubes were rebranded by Sylvania for a number of types.

The current incarnation of WE, owned by Charlie Whitener (sp?), is still making tubes on an irregular basis in the US.  Plans are listed for new 308A's @ over $1,000 each.

The RCA/United 849 was a competitor in many designs.

Dennis

[Chris P.]

Thanks for the info.

Got your email Dave. Thanks!

I had a feeling they wouldn't be cheap, but I had no idea they would be that high.

I need to get it out and check the filament. It has a few large dents on the base. Looks kind of like it was tossed around in a box for a while.

[W2PFY]

And here you can buy on epay (and I do mean pay) a spare for a mere $2495.

That guy is dreaming. He is not a regular seller of tubes and is hoping to score the big one.

[KE6DF]

Right, asking price doesn't necessarily mean much.

You can ask $1M for a 6146 on epay -- but it doesn't mean you will get it.

But 211's, 805's, and 838's selling for three digit dollar amounts are common on epay.

For some reason, 810's are relatively cheap.

Even 8000's are usually cheap but they come up only a few times per year.

But weird things happen.

A while back I bought a NOS 211 (vt-4c) for $20 on epay. Someone listed it at $20 as a buy-it-now and I happened to run across the list only minutes after he posted it -- and bought it immediately.

So not knowing what you are selling cuts both ways sometimes.

[WZ1M]

212A/D/E, Western Electric. AKA VT-6, CW-1819. Power triode, T-28 bulb. Special 4 pin base. 13 volt fil @ 6.265 A. 250 watt.
Hope this helps.
Gary

[KE6DF]

Here is a bit more data on the 212E.

From the Idaho school of mines web archive site. Must be in the public domain, so I'll post the page.

[W2XR]

Right, asking price doesn't necessarily mean much.

You can ask $1M for a 6146 on epay -- but it doesn't mean you will get it.

But 211's, 805's, and 838's selling for three digit dollar amounts are common on epay.

For some reason, 810's are relatively cheap.

Even 8000's are usually cheap but they come up only a few times per year.

But weird things happen.

A while back I bought a NOS 211 (vt-4c) for $20 on epay. Someone listed it at $20 as a buy-it-now and I happened to run across the list only minutes after he posted it -- and bought it immediately.

So not knowing what you are selling cuts both ways sometimes.

The audio enthusiasts want directly heated power triodes that can be biased for class A or class AB service.

Tubes typically utilized in class B audio service (810s come to mind) are generally not desirable from their standpoint. The 833A for some reason seems to be an exception. Audio guys will pay big $$$ for them, particularly those manufactured by RCA.

Just my 2 cents.

73 & Merry Christmas to All!

Bruce

[W2PFY]

From the Idaho school of mines web archive site. Must be in the public domain, so I'll post the page.

Would you please send me the link to that vacuum tube site?

Thanks Terry

[KE6DF]

Here is the link to the old handbooks:

http://www.mines.uidaho.edu/~glowbugs/books/index.html

Here is some more stuff from the Glowbugs mail list:

http://www.mines.uidaho.edu/~glowbugs/

Dave