I will use custom made alumina ceramic pads that vodomore brought to our attention several pages ago. They would surely shatter under very high pressure. As many Tokin SITs are happily working in the various DIY amplifiers that is confirmation enough that any pad + some thermal paste is OK, as SIT has big surface for heat transfer
I'm thinking it would depend on the extremity of the convexity. Have you measured it? I haven't but in my case if there's any it's so small I'm not worried about it.
Maybe I'm worrying too mutch.
The big gap if I screw up two Tokins together, is about 0.5 mm at the screwholes. If I measure gap perpendicular to the SITs longer side, it is decreases in a short way below 0.05 mm.
It is quite interesting at the same time, if I try to measure at the shorter side, I almost able to put through 0.05mm gap meter.
So this side is concave a littlebit.
I think, Soundhappy is right, when he recommend Kerafoil.
Mica too hard in this case, while Kerafoil 0.25 will be able to fill the gap.
Yet, it would be nice, if we know the recommended torque settings.
The big gap if I screw up two Tokins together, is about 0.5 mm at the screwholes. If I measure gap perpendicular to the SITs longer side, it is decreases in a short way below 0.05 mm.
It is quite interesting at the same time, if I try to measure at the shorter side, I almost able to put through 0.05mm gap meter.
So this side is concave a littlebit.
I think, Soundhappy is right, when he recommend Kerafoil.
Mica too hard in this case, while Kerafoil 0.25 will be able to fill the gap.
Yet, it would be nice, if we know the recommended torque settings.
My preference is for Mica over Sil Pads and just enough torque but not too much is perfect for both. 😉 😀
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It's the same Kerafoll=Keratherm Red was used by Ucle Mike
datasheet from Conrad https://asset.conrad.com/media10/ad...-film-025-mm-65-wmk-l-x-w-100-mm-x-100-mm.pdf
datasheet from Conrad https://asset.conrad.com/media10/ad...-film-025-mm-65-wmk-l-x-w-100-mm-x-100-mm.pdf
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on some SITs I have, while using them in prototypes and making amps, ear ends were slightly down, so preventing flat part to get to heatsink
flat pliers, no worries
flat pliers, no worries
I thought I spotted a torque spec over in the V-FET/SIT data sheet thread, but I can't seem to find it now. 🙁
Transistor manufacturers recommend mounting screw torque settings of between 0.8Nm and 1.0Nm. Passlabs use 0.9Nm. This has been discussed in another thread a week or so ago. Zen Mod posted some links to manufacturer specs.
I've just bought these. Never used the seller before but it's not exactly expensive.
CONDENSER MICA INSULATOR LOT=50 SHEETS (40x50x0.04)mm ~(1.58x2.03x0.0014) inch | eBay
PS.
Happy to gift a few.
CONDENSER MICA INSULATOR LOT=50 SHEETS (40x50x0.04)mm ~(1.58x2.03x0.0014) inch | eBay
PS.
Happy to gift a few.
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Perfection is in the eye of the DIYer.
That said, small adjustments will usually improve the result matching.
Thanks
Some 80's pricing on them and a handbook that was available back then. 🙂
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Just came across this thread. Just what I need. I have some Sony SIT,s from the singapore supplier. I just thought I would get some while I could but had no plans to use them then.
Now I want to build power buffer for a DHT valve headphone amp which I like, to turn it into a power amp. Its got a low o/p impedance from its hybrid mu follower o/p which would drive the fet,s I was thinking of using but then I saw this. Bingo! Cant wait !
Now I want to build power buffer for a DHT valve headphone amp which I like, to turn it into a power amp. Its got a low o/p impedance from its hybrid mu follower o/p which would drive the fet,s I was thinking of using but then I saw this. Bingo! Cant wait !
I never would have guessed at the huge price difference between the little guys and the big guys. Triple the current and six times the price.
I also see EEP was on on Manchester Ave. in LA, the same street as Altec Lansing and a stone's throw from Disneyland.
Curve traced my SITs.
First pic, THF-51S matched quad, with papers.
Second pic, THF-51S roughly matched quads.
Third pic, 2SK180 roughly matched quads.
Fourth pic, first and second on one pic.
First pic, THF-51S matched quad, with papers.
Second pic, THF-51S roughly matched quads.
Third pic, 2SK180 roughly matched quads.
Fourth pic, first and second on one pic.
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Excuse my ignorance, but I am not an engineer and I have skimmed through the whole of this thread and perhaps I have missed it, but will it be better to buy a matched pair of the THF-51S or the 2SK180 from watanabetomoaki to potentially participate in this build once it is released?