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Is EC83 the same tube as 12ax7?

Started by pyromaniac_, May 21, 2010, 01:54:58 PM

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pyromaniac_

Hi, I've tried to find out using google, but I didn't got any convincing answers there. The thing is that I've just found some old vacuum tubes, EC83 and EC82 (didn't remember the fabricate but it doesn't matter anyway). And if I'm right the EC83 is the same tube as the 12ax7 and the EC82 is the same as 12au7. Or not?

Don't know much about how tubes are named and so but I can't understand the point with having two part names for the same tube. So is there anything thing else that differs, or is EC83 just the same tube as 12ax7?

tonyharker

As I understand it the ECC83 is the same as the 12AX7.  The EC83 if it follows European nomenclature should be only a single triode not a double like the 12AX7.  The E stands for the heater voltage (6.3v) and the C for the type of tube ie triode.  if it was an F it would be a Pentode as in EF84.

Similarly for the EC82.

Tont

mensur

Quote from: pyromaniac_ on May 21, 2010, 01:54:58 PM
Hi, I've tried to find out using google, but I didn't got any convincing answers there. The thing is that I've just found some old vacuum tubes, EC83 and EC82 (didn't remember the fabricate but it doesn't matter anyway). And if I'm right the EC83 is the same tube as the 12ax7 and the EC82 is the same as 12au7. Or not?

Don't know much about how tubes are named and so but I can't understand the point with having two part names for the same tube. So is there anything thing else that differs, or is EC83 just the same tube as 12ax7?
You must be wrong, cause there is no tube with that name, there are ECC83(same as 12AX7, but just Europian name for it), ECL83 which is triode/pentode (almost the same as 12AX7 in triode section, and weaker EL84 on the pentode section). Maybe one of the letters fell off?


J M Fahey

#4
The base pins and type should clear the doubt. One or two plates (single/double tube) can easily be seen through the glass. Post a couple pictures.
EDIT: the EC83 is a joke. I had thought it would be a 7 pin tube, similar to 6AV6, but it uses 2 pins per element (crazy) to occupy 8 of 9 pins available. What were they thinking? Anyway the existence of 1 or 2 plates still stands.

pyromaniac_

Quote from: mensur on May 21, 2010, 05:12:23 PM
You must be wrong, cause there is no tube with that name, there are ECC83(same as 12AX7, but just Europian name for it), ECL83 which is triode/pentode (almost the same as 12AX7 in triode section, and weaker EL84 on the pentode section). Maybe one of the letters fell off?


Maybe your right, I'll double check tomorrow if I get the time. The tubes is at my grandpas workshop, there I found then. This means that they could be old, really old. So if there ever been a EC83 tube, it could be there. But I doubt it though, the pins looked the same as the 12AX7 (9 pins, noval sockel).

Enzo

Why are there two names?  Why do I call it "Germany" and the folks there call it "Deutschland?"

ECC83 is the European numbering system label for what we call 12AX7 in the USA.  Look at the page in the RCA tube manual, it says "12AX7/ECC83."

All the wondering about odd tubes that EC83 might mean aside, I am pretty sure you mean ECC83 - two Cs - as that is a common tube.  And if you google ECC83 instead of EC83, I bet you find all manner of 12AX7 information with it.


Now there are tube marketers like Groove Tube that make "both" 12AX7 and ECC83, but what they are doing is trying to come up with different names for each of the 12AX7 varieties they sell.   They are all 12AX7s.

pyromaniac_

Thanks for the replies I think that I finally understand now. I just came back from the workshop and of course it was ECC83 the tube was named. And the other tube was actually named E82CC which is the same as 12AU7.

Jack1962

the EC83 is a single triode and the 12AX7 is a dual , the same as the ECC83 .To answer your question no they are not the same

                                                Rock On

mandu

ECCxx and ExxCC may look same, but they have different heater elements.
ExxCC has a 10,000 hour long life filament against 1000 hours for the ECCxx.
ExxCC was considered as industry/military grade tube those days.
Rest of the specs were the same.
regards,
Mandu