Tube ID

[Tgasboy]

Hi Folks,

I'm new here at diyAudio so Hi!

Wondering if anyone can tell me about this tube. It's a Philco 6SL7 chrome glass. Sorry I only have this 1 picture. It has a an octagon shape on the top of the valve.

Who made them, what era etc



Thanks

 

[jsfinusa]

Brent Jessee's Web Site has fantastic info on these and most other audio tubes. Look here for his page on this tube:

6SL7 VACUUM TUBES IN STOCK

 

[Tgasboy]

Yes he does have a lot of good info. I can't see any info about Philco tubes or particularly this type.

 

[316a]

Probably Sylvania

 

[Tubelab_com]

It has a an octagon shape on the top of the valve.

A stop sign shape with the type number inside is a strong clue that the tube was made by RCA.

Sylvania will have the type number with the letters U.S.A. or sometimes USA under it. Later Sylvanias after the Philips / ECG connection are a wild card, anything goes including sweep tubes rewired remarked as 6B4GA's and 7027A's stuffed inside 6BG6GA's.

GE made tubes will have several dots etched into the glass under the type number.

A short fat octagon containing the type number on tubes from the 60's and 70's is Japanese, usually Hitachi, sometimes National / Panasonic. This tube is too old to be Japanese.

It is not uncommon to find tubes from the major manufacturers made by a compettitor. Philco, Motorola and other OEM's did not make their own tubes.

 

[Tgasboy]

Thanks for that onfo. I got the tube for $20 nz and will have it in a few days. Cheers.

A stop sign shape with the type number inside is a strong clue that the tube was made by RCA.

Sylvania will have the type number with the letters U.S.A. or sometimes USA under it. Later Sylvanias after the Philips / ECG connection are a wild card, anything goes including sweep tubes rewired remarked as 6B4GA's and 7027A's stuffed inside 6BG6GA's.

GE made tubes will have several dots etched into the glass under the type number.

A short fat octagon containing the type number on tubes from the 60's and 70's is Japanese, usually Hitachi, sometimes National / Panasonic. This tube is too old to be Japanese.

It is not uncommon to find tubes from the major manufacturers made by a compettitor. Philco, Motorola and other OEM's did not make their own tubes.