A totally tubular afternoon....................

[dread31]

Beautiful day to set up outside, open all of the windows, crank tunes and test tubes on the patio.......The things we geeks do for fun.

Finally borrowed a tube tester from a co-worker of mine and started going through the inventory.

Unfortunately, I still could not test the 6LQ6 or 6GF7 and 6GF7a tubes I acquired a couple weeks ago. Although they all appear to be in great shape.

I did find some interesting tubes in my stash that all tested good, however.

Lots of 6BQ5s;

1-RCA (USA)

1-United Electron (USA)

4-Realistic Gold Pins, Print not so good, but mostly readable. There is a slight brownish smokiness to the glass. I believe these are Japanese. But, they have some weight to them and appear to be nice, high quality. Anyone have more info on these guys?

2-NEC-Unremarkable, but in excellent shape.

Everyone of these 6BQ5s tested above 95%, two of the Realistics @ 98%.

Also found,

2-RCA-7025 (USA)
2-Sylvania-7025 (USA)
1-GE-12AX7 (USA)
1-Sylvania-12AX7 (USA)
2-NEC-12AD7 (Japan)

All tested 80% and higher.

As I understand it, the 7025 was a low noise, more rugged version of the 12AX7. Has anyone here run them in place of a 12AX7?

Lastly,

1-Telefunken EZ80-Telefunken logo gone, but "EZ80" designation still visible. Tests good at 79%.

1-Mystery tube, that appears to be a Telefunken with the "Diamond Base"- The number "20" inside the diamond. Also appears to be a rectifier. All of the print is gone.(See attached photos.)

Dave

 

[audiodon]

7025s are good. They're best for things like phono stages.

 

[dread31]

Yep, that was the first thing that came to mind.

 

[njcanuck]

I don't get it - what's geeky about that? :scratch2:

 

[dread31]

So, can anyone identify that tube for me?

 

[Tom Bavis]

Looks like an EZ80 - not tall enough to be an EZ81...

 

[dread31]

It's the same height as the EZ80, but, the guts look slightly different. Probably just a variation of the same beast.

 

[GordonW]

Could possibly be an EZ82. Less common, but sometimes you still find one here and there. Both the EZ80 and EZ82 cross-reference to the 6V4, so they're essentially the "same"...

That said- I'd guess it may just be a production variation of the EZ80... depending on what year they were made, the internal structure can have "cosmetic" differences...

Regards,
Gordon.

 

[dewdude]

Also appears to be a rectifier.

It looks just like the internal construction of my Sovtek 5Y3's.

-Jay