I was looking at some auctions for NOS tubes. One such auction has the description: "Matched Pair NOS Siemens EL34 tubes." They appear to be from the '70s or '80s. So they're at least 30 years old. No other information about them, for example how they test. So I sent the seller a message:
ME:
What do the tubes measure? Are they tested?
HIM:
I do not know the numbers as these were tested years ago when I was doing
Dynaco Mark IVs and Marshal amps. They were NOS and matched so I did not
have a reason to store the numbers with them. NOS and matched, the numbers
are not needed.
ME:
I think the number are needed. If the tubes are "matched" but still test
well below spec or 100% of what a new tube should read, then that changes
things... If a new tube should read (for example) 80mA @ 450v on the plate,
and these read only 50mA, then they are bad tubes.
HIM:
They are brand new tubes.
ME:
Well unless you can tell me what they test at, I have no way of knowing
that. Isn't that's why most people selling tubes list how they test @ a specific
plate voltage? But all the best with your sale, thanks!
HIM:
You are the type of person that nothing will satisfy get a life.
Tube characteristics will remain stable down to 70% of their original cathode coating.
That being said, the less info is available on them, the less confident i would be.
After the second message from him "these are brand new tubes" I think you should stop. After that you're sort of being a dick. Clearly the guy either doesn't know, doesn't know how, or doesn't care, so why rub it in? It's not a big deal but it's just a waste of time adding your last message except to give him the business.
I was looking at some auctions for NOS tubes. One such auction has the description: "Matched Pair NOS Siemens EL34 tubes." They appear to be from the '70s or '80s. So they're at least 30 years old. No other information about them, for example how they test. So I sent the seller a message:
ME:
What do the tubes measure? Are they tested?
HIM:
I do not know the numbers as these were tested years ago when I was doing
Dynaco Mark IVs and Marshal amps. They were NOS and matched so I did not
have a reason to store the numbers with them. NOS and matched, the numbers
are not needed.
ME:
I think the number are needed. If the tubes are "matched" but still test
well below spec or 100% of what a new tube should read, then that changes
things... If a new tube should read (for example) 80mA @ 450v on the plate,
and these read only 50mA, then they are bad tubes.
HIM:
They are brand new tubes.
ME:
Well unless you can tell me what they test at, I have no way of knowing
that. Isn't that's why most people selling tubes list how they test @ a specific
plate voltage? But all the best with your sale, thanks!
HIM:
You are the type of person that nothing will satisfy get a life.
Tube characteristics will remain stable down to 70% of their original cathode coating.
That being said, the less info is available on them, the less confident i would be.
Yeah that's why I was a little weary. They was just really reluctant to give me any information. There was another auction as well where the description said "NOS, tested really good!" When I asked what the measurements were the guy said he couldn't get any because his "tester was out for repair." So does that mean he never tested them to begin with? Or what. Probably that he tested them at one point but never wrote down the actual measurements. But I passed on that one too.
I found a seller that had all the info when I asked:
Tubes were tested on a calibrated vintage L3-3 (USSR, Kalibr) at Uh=6.3V, Up=250V, Ug2=250V, Ug1=-12.2V
Whenever I bought NOS glass, the tube tester and the MA / or tester ratings were supplied by the seller in the ad, auction, ec. In most cases, those #'s are on the boxes, or taped onto the tubes.
But I've only been buying NOS glass for a dozen years...maybe that's just what I've come to expect since 2001/2002 because I'm a dick.
Whenever I bought NOS glass, the tube tester and the MA / or tester ratings were supplied by the seller in the ad, auction, ec. In most cases, those #'s are on the boxes, or taped onto the tubes.
But I've only been buying NOS glass for a dozen years...maybe that's just what I've come to expect since 2001/2002 because I'm a dick.