Help with EL34 brand Identification

[eleventeen]

Can anyone help identify the brand of the two outer EL34's in this pix? Obviously the middle one is an Amperex, but I have never seen the brand ID of the two outermost "Made in Germany" EL34. Looks like a single getter. The slots in the sides of the plates are a teensy bit narrower than those in the Amperex. I can't really see the flange where the two halves of the plate are flattened together in either example, but they appear NOT to be "see-thru" crimps. Many thanks!

[Ritchie200]

Looks like the old CEI brand.  They re-branded a lot of manufacturers.  Does it have the Telefunken diamond on the base by the pins?

Jim

[FYL]

Inverted IEC CEI print. Welded plates, small rectangular plate holes, dual round getter, teeth on bottom mica: typical of Philips-sourced parts with Eastern European glass and micas.

I'd say they could be from Polam, made in Warsav, Poland in the "Rosa Luxemburg" Philips-run factory, imported in Eastern Germany and then silk-screened with "Made in Germany".

Here's a pic from the Tube World web site, showing two Polam EL34s. One is marked "Made in England"...



And here's a visit to the abandoned Polam factory : http://weburbanist.com/2010/01/20/52-photos-of-a-poisonous-abandoned-factory-enter-die/

Edit: corrected a typo

[eleventeen]

Hmmm. I saw some pix of those POLAMs but the two slots in the plates appear to be the wider type, more like the Amperex. Yes, I tried to imagine the brand logo IEC inverted, but I can't quite get there. Another aspect which I can't see but could ask about in whether there is a hole in the center of the octal key on the base.

These are being offered to me reasonably cheap, of course, as-is, untested. I am thinking I'd take them and bear the risk of deadness if they were primary brand but as mystery tubes I may well pass. THREE of them. Makes it easy, huh? Perhaps they came from a triple-ended ABC class public address amplifier used by the Stasi to broadcast "suggestions" from roving Trabant education vehicles.

Thanks for the ideas anyway, folks.

[Ritchie200]

Here is a shot of the old CEI (second from right).  THe slot size and spacing looks close.  I have also seen several iterations of the CEI brand.  The old stuff was all West German manufacture.  Later some of the Communist makes were branded with every name in the book.  Maybe it's good to pass on this one!  Or do you have a push-pull-push application?

Jim

[eleventeen]

Yeah, that branding on the 2nd to the rightmost was what I was imagining and appears to be the best candidate.

Can you imagine a three-(output)-phase amplifier? How weird would that be? Let's see, we'll move the hum solidly into audio range, use 3x output trannys instead of one; the phase splitter would be something to behold...Hey, fire up the soldering iron!

[Ritchie200]

Don't laugh, necessity is the mother of invention!  If it sounds good, I want dibs on the design!

Jim

[FYL]

Yes, I tried to imagine the brand logo IEC inverted, but I can't quite get there.

CEI (Calvert Electronics Industries), not IEC - my typo, my bad.