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E88CC turbo

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* linear
* 9-pin
* double(!)-triode
* higher mu than E88CC?
* higher S than E88CC?

5 clear criteria


The 8203is
- not very linear
- not a 9 pin
- not a double triode

and it has

- mu between 30 and 35, as opposed to 33 for the E88CC, and
- S that varies from 6,000 to 13,000 as opposed to 10,000 to 15,000 for the E88CC

Otherwise it's perfect!
 
That one seems interesting. Too bad there are no datasheets or curves available. Maybe you measured one?

Quite expensive though. Cheapest NOS I could find was 16,50 USD.

Yes, I have. probably have 15 or 20 of them on hand. I'll check my lab notebook this weekend, but I distinctly remember the distortion being a little higher than a good ECC88 (but MUCH lower than a 6ES8).

These days, $16.50 isn't bad for a tube. I'm about to EBay some EL37, now that I saw what they sell for; my goodness, it's a nice tube, but $200 (what I've seen as the going price) is silly money. I can buy 30 "super" 6BG6 for that!
 
Dearest Dsavitsk,
I hope you didn't jump too quickly to post.

<<mu between 30 and 35, as opposed to 33 for the E88CC>>
The RCA data shows the amplification factor to be up to as high as 40

<<S that varies from 6,000 to 13,000 as opposed to 10,000 to 15,000 for the E88CC>>
Again, the RCA data show Transconductance up to 20,000 micromhos

The 8203 is
<< not very linear>>
I feel it is with a CCS (Gary Pimm ccs), which is how I used it

<< not a 9 pin, not a double triode>>
Correct; I should have said that it is small enough that someone clever, like yourself, could make up an adapter socket. I did that though to an octal.
Others have written that nuvisters are micophonic but that hasn't been my experience, but I have found that the wee buggers love to oscillate.
tim
 
6F12P (6Ф12П) -- if to triodize a pentode half it is almost identical triode.
Mu=100, S=19 mA/V
I have used this in a phono pre which I built for my father with the triode as input and the pentode triode-wired as second stage. A high gain low noise differential phono with only 4 tubes. The only problem is that the rather poor quality pins of this tube means there can be sometimes an intermittant noise(very low level) from less than ideal pin connection. Any suggestions for improving this aspect? It has never been a problem with any of the real military Soviet tubes which I use with their wonderful pin quality-I wonder what that lustrous plating is? The 6F12P (and the 6J52P for that matter) do not seem to be available in military spec versions.
 
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