Let's pool our resources to find some used SITs, power JFETs etc

Adason. Sorry for misinterpreting (Yes I have some Lu1014, I know the part, would like to get copper strata placement boards).
As for the so-called THF51 that I got from the ALIpages, they are an NPN as my tester says, with a considerable gate current drive - the tester said µ=2, I measured Hfe 200* - 350*(warm). It is an NPN, fancy 'new device THF51' is just a scam.

- Test jig - an 8Ω resistor on the source (=emitter), a 5K pot for the gate (=base) and an ammeter in the gate lead. I just set it up such that if it is a SIT, that would show this way; output current would be self limiting; my "lab source" limits at around 1,4A.)
To double test my setting, I tested the 2N3055 same way.
(Invalid test. I did not have a constant Vce, please understand. Just comparative.)
 

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    Informal test of a so-called THF51.png
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can't be giving the name (shrouded in history) but I had the choice of old and new and was so stupid to believe new was well sort of new old stock.
Anyway, nowadays I saw 2SK182 pucks advertised as thyristor, and be sure that is what it will test like - a rather hefty one. it is confusing for the layman.
 
I just bought a quad of "very closely matched" THF51's from Japan. Even have the curves for each device.
Curves would make a 300B jealous. Not cheap but I believe them to be authentic. Test as J-Fets on my not
so fancy tester. If I can finish my F5T mono blocks I want to try a MZM creation next. Have a 3U and 5U deluxe
case standing by 🙂
 
Take a look at the curve data in the attachment. The 300B curves are nearly perfect copies of each other, at equal spacing. That's not the case for the SITs. The 300B is much more linear.
 

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  • 2SJ28.png
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  • THF51.png
    THF51.png
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