Nice triode

[revintage]

Found this one when poking around. It is available but on the border to unobtainium. Ri=2k, mu=30, S=14. Curves look nice I think.

 

[barretter]

And it will remain unobtainable for the rest of us as you haven't told us its name.

 

[SY]

Looks like one of the Russian ECC88 variants. You could get pretty similar curves (maybe a little higher gm) by paralleling two "normal" ECC88 sections.

 

[barretter]

Well I don't think you could call Russian ECC88 variants "unobtainable". You can get similar curves from a triode connected E55L with similar mu, but lower anode impedance and much higher gm ; and they are more unobtainable.

 

[revintage]

Hey SY,
Can admit it looks quite 88ish but with very good linearity at lower voltages(swings down to 10V at 5ma).

 

[barretter]

Is it some kind of state secret?

 

[revintage]

No, it´s just for fun!

 

[kevinkr]

"No, it´s just for fun !"

I.E. I suspect Lars wants you to guess what it is..

The hobbyist group I belong to occasionally plays the same game on its listserv, and someone almost always eventually comes up with the correct id..

 

[Zen Mod]

I'm suspicious because of T=25C

must be some hidden catch

 

[revintage]

Zen Mod,
Forgot to remove that one......

 

[Arnulf]

I'm suspicious because of T=25C

must be some hidden catch

... and all the curves crash right into Ia = 0 line. I've seen such curves not that long ago in one of those threads about "FETrons" and other SS tube substitutes but I don't feel like digging for it. IIRC it had a pretty color drawing from LTSpice simulation, perhaps somebody else will remember it.

 

[Michael Koster]

What are it's interelectrode capacitances?

What are it's electrodes called? ;-)

 

[Wavebourn]

The tube is called Fantasatron. I knew that.

 

[rotaspec]

2n3055 ?

 

[Arnulf]

2N3055 is a NPN BJT.

It looks like (a simulation of ?) depletion mode FET (JFET), possibly with drain to gate feedback.

 

[StevenOH]

Revintage, is it fair to come to the Tubes section and tease unsuspecting tube fans with an old Sony V-JFET?:

 

[funkytek]

Zen Mod,
Forgot to remove that one......

Yup, that's a tell for sure.
Something Si-lly going on

 

[revintage]

OK guys,
You got me . It´s Sonys old V-FET 2SK79.

Enjoy the data-sheet.

Anyway I got amazed when I saw it. Why don´t they continue to make tubelike sand?

 

[sulcorebutia]

OK guys,
You got me . It´s Sonys old V-FET 2SK79.

Enjoy the data-sheet.

Anyway I got amazed when I saw it. Why don´t they continue to make tubelike sand?

It reminds of the recent hype of 2SK70.

 

[revintage]

It reminds of the recent hype of 2SK70

Those devices doesn´t look that promising but on the other hand they are power-FETs.

This thread has now gone overboard into OT but here are the only curves of 2SK60/70 I´ve found.