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IC-style double triode

PostPosted: Tue Sep 06, 2016 10:35 pm
by johntheboffin
I was shown one of these the other day. It is a double triode - operates on Va = 10 V, Vf = 0.7 V but behaves a bit like an ECC88.

nutube.JPG


I had no idea that such things existed.

John

Re: IC-style double triode

PostPosted: Tue Sep 06, 2016 10:56 pm
by Herald1360
It's fascinating but seriously low power- Pa max is 1.7mW. It also works in class A2 (positive grid bias) with an input resistance of about 200K.

It seems to be touted more as a "nice sounding distortion generator" than anything else. The characteristic curves look much like those for conventional triodes but at lower Va and much lower power.

Re: IC-style double triode

PostPosted: Wed Sep 07, 2016 8:29 am
by turretslug
It is an interesting "development"- but more prosaically, might reflect that VFDs (one of my favourite display technologies and one of the last outposts of thermionics!) are a diminishing market and teensy-weensy triodes represents a relatively low-risk toe-in-the-water in a market that craves "toob sound". It's obviously based on existing VFD fabrication techniques and experimenters have been exploiting the triode nature of the devices for a long time. I put development in parentheses as I can't help thinking it simply represents where battery valves would have been in about the early/mid 'sixties if the transistor hadn't appeared. Indeed, I suspect that tiny valves/thermionic ICs were on quite a few drawing boards and development labs on both sides of the Cold War but we just didn't get the full story.

Re: IC-style double triode

PostPosted: Wed Sep 07, 2016 9:24 am
by Cathovisor
turretslug wrote:It is an interesting "development"- but more prosaically, might reflect that VFDs (one of my favourite display technologies and one of the last outposts of thermionics!)

Snap! I love VFDs - so elegant and attractive.

Re: IC-style double triode

PostPosted: Wed Sep 07, 2016 10:29 am
by Dr Wobble
Weird. I guess it's intended for some sort of guitar gear as it's made by Korg, maybe in a guitar pedal.

Never played about with VFD's. I intended to, having got one off an old video recorder, but I put it somewhere safe and havn't seen it since despite several searches.

Thanks for sharing John, I'll see if I can find anything more out.

Andy.

Re: IC-style double triode

PostPosted: Wed Sep 07, 2016 8:41 pm
by Lloyd
Not so long ago you could get a VFD from Maplins in a mixed bag of displays for £4.99. I think they may still have them, best to look in store rather than online as at least you get to pick the bag containing the display you want! I bought some to repair a VFD clock that I stupidly dropped and broke :aaf

Regards,
Lloyd.