se-output-trans-calc-1
Afer read it some times, you can design OPT for everything and find out nothing is more exciting and easier than building SS OPT.
Afer read it some times, you can design OPT for everything and find out nothing is more exciting and easier than building SS OPT.
it'll work
you don't need that 10-15K from gate to gnd
also - your heatspreader plate isn't thick and long enough
L bracket is so-so .......
solve it using longer L bracket alone , without additional heat spreader plate
you don't need that 10-15K from gate to gnd
also - your heatspreader plate isn't thick and long enough
L bracket is so-so .......
solve it using longer L bracket alone , without additional heat spreader plate
Tks Mr. ZM! You are right.
I think lot about that 10k res.
In SIT Amp I will use JT-11p-1TB as input trans at first test because I believe in it and know exactly its sound. http://www.jensen-transformers.com/wp-content/uploads/2014/08/jt-11p-1.pdf
In FT-11P- 1xx 10k/10k type, Jensen alway say "RL must be 10k or greater for ......... " and JS use Rs=600r and Rl= 10k in all test.
In SIT Amp with 1:1 10k input trans without Rl or Ironamp, input impedance seem floating because input trans behave like repeat_coil I think so and I want to have a test. When I build Ironamp, it sound extremly beautiful immediatly so I don't dare to change anything event resolder some ugly point ... SIT amp give me a chance to test that 10k res.
I think lot about that 10k res.
In SIT Amp I will use JT-11p-1TB as input trans at first test because I believe in it and know exactly its sound. http://www.jensen-transformers.com/wp-content/uploads/2014/08/jt-11p-1.pdf
In FT-11P- 1xx 10k/10k type, Jensen alway say "RL must be 10k or greater for ......... " and JS use Rs=600r and Rl= 10k in all test.
In SIT Amp with 1:1 10k input trans without Rl or Ironamp, input impedance seem floating because input trans behave like repeat_coil I think so and I want to have a test. When I build Ironamp, it sound extremly beautiful immediatly so I don't dare to change anything event resolder some ugly point ... SIT amp give me a chance to test that 10k res.
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Do your 2SK180 sit was tested with curve tracer ?
What is his batch serial number ?
I remember few X, Y, Z series sit's was with less desirable characteristics.
Best regards 🙂
What is his batch serial number ?
I remember few X, Y, Z series sit's was with less desirable characteristics.
Best regards 🙂
Frankentracer tool made by Mr Rothacher are great for tests use with oscilloscope
http://www.diyaudio.com/forums/pass-labs/269379-live-lab-hangout-1-1-posted-34.html#post4290064
http://www.diyaudio.com/forums/pass-labs/269379-live-lab-hangout-1-1-posted-34.html#post4290064
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Thanks soundhappy!
Mine is Z series. Have you ever build something with 2sk180 and did you SIT get hot ?
Best regards!
Mine is Z series. Have you ever build something with 2sk180 and did you SIT get hot ?
Best regards!
@ Jamahamvui1978
With high bias current they run hot normaly...
you can find and read threads here at DiyAudio Forum and visionate videos about 2SK Tokin sit's made by Mr Rothacher at
Audiohobby.com | DIY Audio Projects & More.
I just test my 2SK180 and 2SK182 not builds for the moment.
Be shure you get propery working sit's pair curve tracer test was more specyfication revelating.
Best regards 🙂
I read and vew nearly all articles or videos about SIT of Mr Pass and MR, that why my OPT for SITamp was built to withstand 2A - 64:8 or 4A if use 32:8. Unfortunately, my OPT was beginning to be warm at 2A so I had to reduce bias to 1.8A at first test. I'll increase B+ or try 32:8 later when I "vechai" out parts fit with changes.
If anyone love 211 tube and don't have Pass SIT.1, try SITamp with 2sk180. Even though all my mistakes it sound very great 😀
If anyone love 211 tube and don't have Pass SIT.1, try SITamp with 2sk180. Even though all my mistakes it sound very great 😀
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I found and bought a pair of Tango FG-50S for my friend, these OPT are the same as that I bought two years ago for build my SIT Nemesis with Pass SIT-1 transistors. Now I want to help my friend build the amp use 2SK180 transistor with output transformer.
Hi Mike! With your experience about 2SK180 and the FG-50S specification below, please help me make some quick calculation and tell me the voltages + current bias for the best sweet spot. The primary impedence is 64 ohm (2A), 32 ohm (2A) or 16 ohm (4A).
Thank in advance! 😉
Hi Mike! With your experience about 2SK180 and the FG-50S specification below, please help me make some quick calculation and tell me the voltages + current bias for the best sweet spot. The primary impedence is 64 ohm (2A), 32 ohm (2A) or 16 ohm (4A).
Thank in advance! 😉
Oh, that's a beauty.
Without physically testing, it's hard to say for sure, but maybe I could sim something. Can anyone translate the winding resistances and inductances?
With the 2SK180 it should be pretty similar to the PASS-SIT-1, so you could certainly start there.
Having those other taps will be fun too. 🙂
Without physically testing, it's hard to say for sure, but maybe I could sim something. Can anyone translate the winding resistances and inductances?
With the 2SK180 it should be pretty similar to the PASS-SIT-1, so you could certainly start there.
Having those other taps will be fun too. 🙂
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Hi Mike!
I almost bought all of things for my SIT Nemesis use PASS SIT-1 amp and I hope I will finish in next two or three months. Mr.Pass told me that I should running the PASS SIT-1 transistor with FG-50S at 25VDC + 1A bias and connect to 32 ohm tap. Now, with 2SK180 is high power VFET transistor so I and my friend want to try the higher voltage + higher bias current to create a higher power output for easy to drive some big loudspeakers but we are really don't know sweet spot and which taps for connect. I will use LCR meter and tell you correct Rdc + inductances at each tap soon.
Thanks for your care!
Hi Mike!
I measured the primary windings of FG-50S by DER EE DE-5000 LCR meter with frequency is 100Hz, this is the result:
1/ Tap 64: L = 298mH, Rac = 54.91ohm, Rdc = 1.21ohm
2/ Tap 32: L = 150.83mH, Rac = 27.17ohm, Rdc = 0.89ohm
3/ Tap 16: L = 74.26mH, Rac = 13.30ohm, Rdc = 0.4ohm
I hope it will helpful for you!
I measured the primary windings of FG-50S by DER EE DE-5000 LCR meter with frequency is 100Hz, this is the result:
1/ Tap 64: L = 298mH, Rac = 54.91ohm, Rdc = 1.21ohm
2/ Tap 32: L = 150.83mH, Rac = 27.17ohm, Rdc = 0.89ohm
3/ Tap 16: L = 74.26mH, Rac = 13.30ohm, Rdc = 0.4ohm
I hope it will helpful for you!
So, wanting to keep the 2SK180 under 80W or so:
32-ohm tap, 100V B+ 800mA Id might be a good place to start. That'll get you to 18W or something like that. 🙂
You'll want some supply regulation.
32-ohm tap, 100V B+ 800mA Id might be a good place to start. That'll get you to 18W or something like that. 🙂
You'll want some supply regulation.
Thank you so much for your help!!!
I really have a little surprise with your result. Can you explain a little bit about 32 ohm tap? I just think with 100V B+ and 0.8A bias so the primary impedance must be higher 32 ohm. So sorry for my question, maybe my experience is wrong about this :-(
I really have a little surprise with your result. Can you explain a little bit about 32 ohm tap? I just think with 100V B+ and 0.8A bias so the primary impedance must be higher 32 ohm. So sorry for my question, maybe my experience is wrong about this :-(