Sylvania tube question...

[parkerdom]

Hi, all... I got some single 6SN7's in a trade. One of them is a Sylvania, but I've never seen markings like this. Otherwise it looks like a Sylvania. Please help, friends... thanks.

 

[Catmanboo]

What is it you're asking? Your top shot is flash-compromised.

 

[Mr Boochie]

What is it you're asking? Your top shot is flash-compromised.

I think the white is from the flash of the phone's camera.

It looks like a Sylvania-made tube.

 

[gadget73]

The base markings make me think its probably later production, maybe 1970s, but yeah, looks Sylvania to me.

 

[Mr Boochie]

The base markings make me think its probably later production, maybe 1970s, but yeah, looks Sylvania to me.

The font style does look 1970s and later.

 

[Catmanboo]

Looks like one of the last tubes Sylvania made to me.
Booch, my flash-compromised remark did indeed refer to fone/camera flash image overload.

 

[Mr Boochie]

Looks like one of the last tubes Sylvania made to me.
Booch, my flash-compromised remark did indeed refer to fone/camera flash image overload.

Oh, I thought you meant getter flash.

Sorry!

 

[parkerdom]

Thank you all for your replies, but I should have been more specific. I have no doubt that it's of Sylvania manufacture. The writing on top I've seen before. I found many Sylvanias with the same tube construction, but I couldn't find on the Internet any other Sylvania with the tube designation, brand, "MADE IN U.S.A", and letter codes on the base. I'm mainly interested in what factory and when it was made. And, I'd like to find another with the same markings on the base (different letter codes would be acceptable).

 

[Pio1980]

I think the white is from the flash of the phone's camera.

It looks like a Sylvania-made tube.

View attachment 3210947

It is.

 

[mrwood200]

....... but I couldn't find on the Internet any other Sylvania with the tube designation, brand, "MADE IN U.S.A", and letter codes on the base. I'm mainly interested in what factory and when it was made. And, I'd like to find another with the same markings on the base (different letter codes would be acceptable).

Yes, a little unusual to have all this info on base, but not rare. A lot of military tubes have tube type + more on the base.
There is a similar Sylvania on epay now. Not identical, but:

If you are patient, you should be able to find another with same label.
I cannot tell you what the letters/codes mean. I don't think I have ever seen a key for these symbols