Q Mr. Pass: Found what I was looking for inthe J2 manual
Please share here then, so I don't have to chase it down😀
No miracles
There is not much to say, Tea bag.
In the owners manual papa is showing the distortion graphs. The new devices
are working with 10V and 2A bias current. The pix at 6 moon shows a 10V torriod inside.
It seems Mr Pass is using 2SK389 and 2SJ 109 at the input stage, when he is talking about "not yet available parts". I think he had some bags left in one of his drawers🙂
But I will wait until we will receive an other present from Grandmaster Pass.
I will go on with the Nemesis project
Regards
Sam
There is not much to say, Tea bag.
In the owners manual papa is showing the distortion graphs. The new devices
are working with 10V and 2A bias current. The pix at 6 moon shows a 10V torriod inside.
It seems Mr Pass is using 2SK389 and 2SJ 109 at the input stage, when he is talking about "not yet available parts". I think he had some bags left in one of his drawers🙂
But I will wait until we will receive an other present from Grandmaster Pass.
I will go on with the Nemesis project
Regards
Sam
thanks for those hints.
I will look for the pics again, but the 10v @ 2amp I think refers to the modified F2 with the replacements. Older F2 uses 13.5v I think. This might suggest a different source DC voltage.
I will look for the pics again, but the 10v @ 2amp I think refers to the modified F2 with the replacements. Older F2 uses 13.5v I think. This might suggest a different source DC voltage.
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I can't put my hand in fire for that , but I'm still pretty sure that Papa use 2x18V
plitron in J2
sorry - my secret agent in FW is on vacation these days , and hers cellphone is on off

plitron in J2
sorry - my secret agent in FW is on vacation these days , and hers cellphone is on off

Expensive devices. I imagine the price will come down in time.
if they live long enough ; just remember what happened to LUs
Thanks for th info ZenMod!
Yes it seems that Mr. Pass tries to keep his stock of parts clear.
I don't have a distorsion analyser. Does somebody have built the unit of Ron Elliott?
Regards
Sam
Yes it seems that Mr. Pass tries to keep his stock of parts clear.
I don't have a distorsion analyser. Does somebody have built the unit of Ron Elliott?
Regards
Sam
Main problem of such devices is the reason why they exist at the first place.if they live long enough ; just remember what happened to LUs
In attempt to use "NEW" material instead of silicon, simpliest devices
are manufactured first - CREE and others just can not produce decent
MOSFET yet.
But JFET are much easier to make - at least that's what they say...
I'm not quite sure about your conclusion Alex.
Trouble is that the market for such devices, evolves at a hefty pace, thus the niche manufacturers don't have the luxury of a steady market, which in turns results in products coming and going.
I saw that coming with the LU's, and bought a hefty stock.
Now I'm real happy I did so, and in a few years, I'm most likely going to be even happier about it 😀
Magura 🙂
Trouble is that the market for such devices, evolves at a hefty pace, thus the niche manufacturers don't have the luxury of a steady market, which in turns results in products coming and going.
I saw that coming with the LU's, and bought a hefty stock.
Now I'm real happy I did so, and in a few years, I'm most likely going to be even happier about it 😀
Magura 🙂
I'm not quite sure about your conclusion Alex.
Trouble is that the market for such devices, evolves at a hefty pace, thus the niche manufacturers don't have the luxury of a steady market, which in turns results in products coming and going.
I saw that coming with the LU's, and bought a hefty stock.
Now I'm real happy I did so, and in a few years, I'm most likely going to be even happier about it 😀
Magura 🙂
Considering the uses for these new JFEts to build more efficient power supplies & electric cars I would think it's only the beginning of a new generation of these devices. How many are you gonna buy at $60 a piece?
Considering the uses for these new JFEts to build more efficient power supplies & electric cars I would think it's only the beginning of a new generation of these devices. How many are you gonna buy at $60 a piece?
At least 1000? 😉
I can't put my hand in fire for that , but I'm still pretty sure that Papa use 2x18V
plitron in J2
sorry - my secret agent in FW is on vacation these days , and hers cellphone is on off
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I think you are right. The the part number looks like 077014201 which is same as the 2X18 that I have here.
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I think you are right. The the part number looks like 077014201 which is same as the 2X18 that I have here.
well - real fact is more important than fact am I right , or somebody else 😉
and all that - even not considering is it possible to have 30W/8E with 20Vct xformer .....
Papa is damn good , but not so good to make perpetuum mobile ...... even if another breed of HiFi mnfctrrs are often capable to do exactly that ......
🙂
Considering the uses for these new JFEts to build more efficient power supplies & electric cars I would think it's only the beginning of a new generation of these devices. How many are you gonna buy at $60 a piece?
A few 😀
Magura 🙂
I should start a wholesale business with these semiconductors. diyA-members would get a reasonable discount. 😀 Unfortunately my equity ratio is poor! 

My source is PCIM 2009. Reps from companies involved with SiC & GaAs,I'm not quite sure about your conclusion Alex.
Trouble is that the market for such devices, evolves at a hefty pace, thus the niche manufacturers don't have the luxury of a steady market, which in turns results in products coming and going.
I saw that coming with the LU's, and bought a hefty stock.
Now I'm real happy I did so, and in a few years, I'm most likely going to be even happier about it 😀
Magura 🙂
I would not name - you probably know.
What posted is almost the quote. Reasons: unresolved manufacturing problems
and, as you correcly mentioned, price (read: technology penetration needed).
IRF, for instance advertise NEW BREAKTHROUGH devices for more than two years - that's about all.
No product is on avail. I recall SIT & BSIT - where are they?
Even SIC diodes are 20 times more expencive than Si counterpart.
SIT or JFET is inconvinent to control etc.
These guys have about 100X on price and 1000X on volume to go. Just the way things are, no auto manufacturer is going to sign up for a single sourced expensive part like this. Scuttlebutt is that GaN will win in the end anyway.
On another note the enhancement mode operation at the gate is potentially bothersome for linear operation. Still looking for some serious technical literature on details of the characteristics.
On another note the enhancement mode operation at the gate is potentially bothersome for linear operation. Still looking for some serious technical literature on details of the characteristics.
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