Tube identification help

[Mikethenewb]

I pulled this 12ax7 ecc83 from a grundig so 101/60 px. All the markings have worn off. I have put it up next to a Volvo 12ax7 and they look identical. Can anyone confirm? The one on the right is valvo

 

[Dswankey]

Mike

Seeing as the unit you pulled it from is a Grundig my guess is they are German made. Seimens, Valvo, Telefunken, Lorenz are possibilities.

If you have not already seen this it's a great resource for German made tube identification

http://www.tube-classics.de/TC/Tubes/SieTel ECC83/ECC83.htm

Are there any are markings on the bottom between the pins? such as a diamond or wording mC1 mC2?

Any markings on the sides of the glass toward the bottom? sometimes they're hard to notice if you have a flashlight you might be able to discern something.

I've seen numerical marking on the tops of tubes before but I can't remember what they signify with regards to manufacturer ID. I'm sure someone will be along to clarify.

 

[tubevalve]

The four raised lines in the top of the bottle suggest it's a Phillips family valve. Any faint etched code down near the bottom of the side of the bottle?

 

[Mikethenewb]

Here is the code on the bottom

 

[Dswankey]

Ok, now we are getting somewhere. It's a short plate 15mm as opposed to the large plate 17mm

I60
D9F

The I6 indicates it's an ECC83 which we already knew I'm not sure what the 0 stands for.

The 9 indicates 1959, the D is the factory code in this case Valvo/Hamburg and I'm pretty sure the F stands for the month so July

http://www.tube-classics.de/TC/Tubes/Valvo ECC83/ECC83.htm



Here's that tube ^ blown up, notice the angle of the getter is very similar to the one you posted initially

 

[zackthedog]

Yeah, that's a Valvo--beautiful tubes.

 

[Mikethenewb]

How about this one it has the = with a line down the middle and then 7L

 

[Mikethenewb]

I think it is this one form Siemens and Halske that is rare.

 

[Dswankey]

I can't tell based on the pic you posted in post #7.

Here's what I do when I'm taking pics of date/etch codes of tubes. Get a flashlight and shine it on the tube where you hopefully can see something. I usually stand the tube on it's pins or lay it on its side on a piece of cardboard or something like that and with the light on it zoom in best you can to take the pic.

Here's an example



The distance from your hand holding the tube from the camera lens is to far and doesn't reveal anything.

 

[Mikethenewb]

≠7L is the only code on the tube.