Live Lab Hangout #1.1 Posted

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Nelson's instruction are a great start. Do you have a 10 ohm power resistor or something of the sort?

Would a demonstration help?

Thanks Michael.
Yes instruction from Papa are clear and simple to understand.
It is sort of 3 or 5 watts power 10 ohm resistor required or small 1/4 watts do the job too ?
Ready i have at home only 33 ohm 50 watts and 1ohm 25 watts power resistors.
Bench psu are 0-30V , 0-5 A model.
Yes demonstration of test procedure for big sit´s 180, 182 are welcome
it be nice and useful any chance to included in next Lab Hang Out ?
Picture with Tokin source, gate, drain are ok ?
All my best
 

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Well....the ideal solution involves going to your neighbor's house and borrowing a cup of sugar and a 8-10 Ohm 50 (or more) Watt power resistor. If you get a nice big one, you can use it as a dummy load in the future. Every bench should have one. :)


All is writing =< 50 watts 8 and 10 ohms resistors on list must have components.
I am not in hurry to test them and have patience to collected elements for ideal test situation.
Yeah step by step equipements grows maybe oscilloscope for next time :)

After datasheet input capacitance of 2SK180 & 182 ES are the same 2500 pF value
but other 2SK182 ( 1000 watts device not ES one ) have 8000 pF
so one more time i was little confused despite it was mentioned on this forum.
http://www.diyaudio.com/forums/pass-labs/253411-article-sony-vfets-part-1-a-100.html#post4228884
What is show in real lab conditions about 2SK182 ES input capacitance ?
Thanks again for such interesting thread with lots of things to learn.
Have a nice day
 

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This is confusing the 2sk182 is a 1000W round device with that 8000pf input capacitence.
The 2sk182es is a 500W device in a package like a big T03 with 2500 pf.

The 2sk182 has another difference in that it needs to be clamped between 2 heatsinks.
 

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A musical bomb, 150watt is one third of the power. This is a monster transistor, imagine an equivalent valve... You are going on in monster transistors what you wait from them? Michael talked about the envelope of the curves could became more linear with more power and you can wait more than 100watts of power in SE. There are projects with 833 valve that I mean they have less power than this transistor.
Christophe is planning in parallel two of them. Now in winter time is satisfactory to burn Montpelier.
Regards for the French Gemtlemen
 
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The 2SK182 (shown in the graph) is the big hockey puck part and it has much higher capacitance.

The ES is more like the 180.

I'll try to make the distinction more clear in the future.

10 Ohms makes the math easier, but 8 will work just fine too. (>=50W preferably, tho you could get away with something a little smaller)
 
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this seems to be the right place for SE players with the bulky SITs-----:)

this is a simulation I did some months before. The hint to use such a big drain resistor between 40 an 45R came from Mr. Pass itself when I wrote him.

I am not happy with the distortion at 1 Watt/8R, I could get lower but I wanted this nice k2 around 10dB over k3 and this spectra like organ pipes.

It still has to be build. I have already all the caps for the PSU and the bridging of the 5R resistor delivering the negative biasing voltage for the SIT.

But I eschew the money for the Ohmite 100W, so I will simply take two bulbs in series.

I made the SK180 model with the help of Mike R homepage.

:)
 

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and as you can see it is possible in simulation to get distortion lower….

in the case: some like it hot….. :) and lucid

more k3 dominant.

The gain is for both solutions low, not even 4x
 

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