Another tease of Papa Diy upcoming writing's ?
My dream to see complete schematic and build one.
Mixture of SE Aleph J with M2 front-end but with Vfet.
Fascinating elegant circuit. Music sound like pure honey with Feastrex's.
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I have about 50 x 2sj28, they all tested in Mr.Pass'maching circuit by Nagini. B+ = 15v, Id= 0.5A and Vgs were noted and selected pairs and quads. They have Vgs ranges from 4.8 to 12.5V.
Maybe I have to wait for you and study much more about Vfet and circlotron if I want to play Vfet with self-bias, and I hope someone will help newbies the method of calculation self-bias for Vfet too.
eg: If I saw "The SoundHapy" circiut before I would never destroyed JE-123 DL in order to rewind and try the same
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you got pretty much everything - just choose CCS flavor you like
for starters even resistor will do
and , btw. - I can't see any resemblance to Aleph J
Lucky boy to have so many. 🙂 The low Vgs ones will work best in this circuit. Do you have some well-matched pairs in the low range?
Can you point me to that?
This is making me glad I bought an extra couple of edcors when I bought for the M2 clone I've not as yet finished... 🙂
By resemblance to Aleph J i mean not completly,
only because is single-ended power output stage with his active CCS.
Details of the two are different's for sure.
Don't know what transformer is and N channel Vfet , resistors, caps values, CCS semi etc.
Mighty ZM are experienced not piece of cake for me...
Edcors or Jensen's are available & resonable priced
i get few pairs of 2SK82 / 2SJ28 and Tokin 2SK180's.
My decision is not build big greedy balanced amp with 8 pairs so
i try enjoy all minimalistic topologys wonders now.
Have a nice Sunday
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The schematic shows an orphan N-Channel SIT which can readily be rewired to accomodate 2SJ28.
Haha Jamahamvui1978 welcome to the game with 2SK79 | 2SJ28
i guess friendly diyer Nagini and more Diyers joint us
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I also would love to see SIT Aleph style amp.
VGS of my 2SJ28s are marked between 6 and 12V but I forgot how I measured...
It's time for swap market for SIT?
VGS of my 2SJ28s are marked between 6 and 12V but I forgot how I measured...
It's time for swap market for SIT?
Hello claudio52. I find your simple schematic and others like it amazing. Especially when the graph of the electrical characteristics of N-MOS is supeimposed on that of a [re-oriented] P-SIT or N-SIT which is radically different.
It may be possible to lower further your DEF's simulated %THD values by connecting a capacitor between Vout and Vin; granted the output impedance of the signal source is low. This capacitor [say 0.5-15uF] is expected to shunt harmonics from Vout and clean its performance.
Ok but what is channel and reference of CCS transistor and his biger picture circuit , with opto ?
With 2SK79's and KF-33 2SJ28 pair in drawer " The Soundhappy " amp is logical choice .
Such exciting project i can build after Inductor 193V finalisation and Papa CSX1 Vfet.
Thanks a lot Michael i feel like lucky one hope many Diyers too
https://vimeo.com/183344992
Device polarity is always on mind; especially with SITs. I will not contribute to their extinctions.
I have some but they matched pair with 2sk82 for a special party at last, Vfet P.2🙂. There are only 40pcs which I could feel free to play with them .
Vgs :11,9 ; 11,76; 11,56; 11,36; 10,95; 10,79; 10,52; 10,5; 10,37; 10,3; 9,72; 9,63; 9,5; 9,45; 9,4; 9,3; 9,3; 9,19; 9,06; 9,05; 9,01; 8,98; 8,87; 8,86; 8,84; 8,63; 8,57; 8,49; 8,33; 8,14; 8,02; 7,99; 7,92; 7,83, 7,8, 7,76; 7,68; 7,63; 7,27; 7,26
In my case, can we use auto bias in schm(6). I love "simple" but ......😀
I've try my best but could't find out it right now, sorry !🙁
Best Regards
Jamahamvui.
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Hollo Antoinel, thank you for the advice. The scheme is just a virtual play. I think Sony VFET are more suitable in the circuits proposed by Rothacher and Nelson Pass. I'm at the last stage of building a Sony VFET amplifier part 2.
Maybe, for a DEF, the SiC depletion mode N channel JFETs are better suited.
If the extra voltage references don't bother you , then yes, or the V-FETRON with all the polarities flipped.