Found some Tesla tubes that don't seem to match anything I've seen online

[millenium3]

I was going through my tube stash trying to weed out things I don't need and found several Tesla ECC803-S tubes that I don't remember buying (I've been playing with tubes for 30 years). I know Tesla bought equipment from Telefunken when they were shutting down (and apparently also got some instruction on how to use it). I also know Tesla produced some very good tubes that were almost as good as Telefunkens--at least for awhile. At some point JJ got involved and I really don't know what happened after that.

I'm trying to figure out if my stash-discovery is anything worth getting excited about. My understanding is the Telefunken used the ECC803 designation for these kinds of tubes and that Tesla used ECC83 for the same tube. Neither of these match the designation on my tubes. The obvious solution would be to try them out in some decent equipment that used 12AX7 tubes--to hear how they sound, but I don't have anything that uses these tubes. They seem to test reasonably well (but not as close to spec as a Telefunken would have). Here are some specifics:

Short plate
Anode is indented suggesting (but not proving) a frame-grid inside
Yellow paint Tesla Logo & tube identification + the words "Special Quality"
Gold tube pins (the two pictures are of the same tube. I changed the lighting and it changed the color balance on the tube pins)
Top of tube has a flat-ish dome instead of a fully round dome (this shows better in the back-side photo, after I changed the lighting).

Any assistance will be greatly appreciated!

 

[Primotubes]

I have a few of these tubes and I remember that this Tesla brand did buy the tele tube making equipment to make their own copies. Unfortunately the civil war in that part of the country destroyed the factory. I dunno if this copy sounds better or worse than the original Tele but for awhile yoou could buy a very nice sq ecc83

 

[peterh]

There was no civil war in checkoslovakia where tesla was located. Are you mixing up with NIS in serbia/jugoslvakia ?

 

[ceylon]

theres something wrong here.

tesla ECC803S is long plate.

tesla E83CC is a copy of telefunken ECC803S frame grid.

jj is not a continuation of tesla but a separate manufacturer.

your tube sure looks like tesla E83CC, but the print all wrong for a couple reasons:
1. wrong tube type
2. no factory code below tube type.

 

[ceylon]

I have a few of these tubes and I remember that this Tesla brand did buy the tele tube making equipment to make their own copies. Unfortunately the civil war in that part of the country destroyed the factory.

no civil war in czechoslovakia

 

[millenium3]

I also noticed there are no date codes that are typical of Tesla unless the writing on the back (501 A2) means something. I suppose its possible these tubes are fake. But if they are, you would think they would be identical copies of a well-known tube--rather than some mismash of several different tubes. The tubes came in individual boxes that say "Electron Valve, performance tested". Its possible that Electron Valve is/was a company name that sold new and used tubes back when I bought them. I probably bought these in the 1990's when I was building a phono pre-amp.

I do appreciate all the comments. If anyone knows of another forum where my question might be placed, feel free to direct me.

 

[ceylon]

I also noticed there are no date codes that are typical of Tesla unless the writing on the back (501 A2) means something. I suppose its possible these tubes are fake.

i was thinkin that, but i cant imagine what they could be otherwise. only two tubes look like this: tesla E83CC and TF ECC803S. jj's E83CC looks quite different.

But if they are, you would think they would be identical copies of a well-known tube--rather than some mismash of several different tubes.

all the tesla fakes i seen are JJ.

The tubes came in individual boxes that say "Electron Valve, performance tested". Its possible that Electron Valve is/was a company name that sold new and used tubes back when I bought them. I probably bought these in the 1990's when I was building a phono pre-amp.

electron valve is another name for vacuum tube.

I do appreciate all the comments. If anyone knows of another forum where my question might be placed, feel free to direct me.

i cant think of a place where youll get a more thoughtful and well-informed identification.

 

[eiraved]

I do appreciate all the comments. If anyone knows of another forum where my question might be placed, feel free to direct me.

You are in the correct forum.

 

[Primotubes]

There was no civil war in checkoslovakia where tesla was located. Are you mixing up with NIS in serbia/jugoslvakia ?

Perhaps, I thought the Balkan wars affected all of those countries. I know that the Tesla tubes disappeared during that time.

 

[ceylon]

Perhaps, I thought the Balkan wars affected all of those countries. I know that the Tesla tubes disappeared during that time.

czechoslovakia wasnt part of the breakup of yugosavia, and the balkan wars in yugoslavia played no role in the end of tesla production in czechoslovalkia.

EI manufactured tubes in yugoslavia. the breakup of yugoslavia had an effect.

the collapse of the soviet union had an effect on both.

 

[millenium3]

Well...
I found a similar tube on eBay (item number: 236107613954). It's the only other Tesla tube I've seen that uses the ECC 803-S nomenclature. The seller calls it a prototype from 1960. Aside from not having gold pins and "Select Quality" printed on the tube (like mine do), its other distinguishing feature is the size of the anode. Mine has a short plate; his is a long plate. He doesn't show the back side of the tube so you have to read "through the glass" to see the date code (KV). I looked it up and KV does signify 1960 according to a chart I found on the web. My tubes don't have any typical-Tesla date code.

I have determined where my tubes were produced: Trinec is a small city, currently in the Czech Republic, but previously in Czechoslovakia. Most Tesla tubes have a 2-letter code on the front side indicating the location of manufacture. Mine spells out the whole name on the backside.

I am becoming convinced my tubes are not fake. They may be an early version, or some other kind of variant--produced (perhaps) before Tesla adopted the E83CC designation. They could even be a special run of tubes made under contract for a specific client.

Thanks again for everyone's thoughts and comments.

 

[ceylon]

as stated earlier, tesla ecc803s is
long plate. theyre quite common and for sale all over the place. i posted photos earlier.
yours is E83CC frame grid.

yours could
simply be a misprint

 

[millenium3]

Your photos were very helpful! They showed quite a bit of variation amongst different tubes. It was useful to see that not all Tesla tubes had a factory code on the front.

I'm just not sure I'm comfortable with the idea of a "misprint"--especially on tubes the manufacturer is calling Special Quality and going to the trouble of applying gold to the pins.

 

[ceylon]

Your photos were very helpful! They showed quite a bit of variation amongst different tubes. It was useful to see that not all Tesla tubes had a factory code on the front.

they sure do--tesla e83CC and ecc803s, ef86/806S do.

I'm just not sure I'm comfortable with the idea of a "misprint"

your E83CC has "ECC803S" printed on it.

--especially on tubes the manufacturer is calling Special Quality and going to the trouble of applying gold to the pins.

its no trouble its a stock feature: earlier tesla e83cc are gold pins, the later ones not. FYI E83CC means "special quality ECC83"

having ruled out counterfeit as explained above, misprint is most likely. again, the wrong tube type is printed on the tube.