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Old 8th March 2007, 06:38 PM   #1
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Default Jfet Bosoz?

Has anyone experimented with creating a JFET version of the BOSOZ? Seems like an interesting idea. Just wondering if this has any merit.

-David
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Old 8th March 2007, 06:45 PM   #2
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It has a tremendous amount of potential.

While simply hooking up a 2sk389 in that topology actually
works well, it is easy to envision a fully cascoded and
constant current sourced version, with output followers
if you want to "gild the lily"

If there is any enthusiasm, I'll go dig up some of my curves and
get back to you next week.

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Old 8th March 2007, 06:50 PM   #3
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Quote:
Originally posted by Nelson Pass
It has a tremendous amount of potential.

While simply hooking up a 2sk389 in that topology actually
works well, it is easy to envision a fully cascoded and
constant current sourced version, with output followers
if you want to "gild the lily"

If there is any enthusiasm, I'll go dig up some of my curves and
get back to you next week.


I for one would be very intresded in seeing such topology in action. Any posibility that you could post also a schematic? May be this is asking too much

Thanks very much Nelson
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Old 8th March 2007, 07:31 PM   #4
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You can chew on this if you like...

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File Type: jpg bosoz with jfet.jpg (32.0 KB, 3707 views)
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Old 8th March 2007, 07:45 PM   #5
Vix is offline Vix  Yugoslavia
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Wow! Woo!

I started thinking about BOSOZ, Aleph P....and now this one!

Q3-Q6 could be replaced by mosfets CCS, or resistors...

What devices do you recommend for Q1 and Q2? Would LU1014D work in this circuit?

Thanks,

Vix
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Old 8th March 2007, 07:47 PM   #6
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Quote:
Originally posted by Nelson Pass
You can chew on this if you like...


Very chewy!

-David
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Old 8th March 2007, 07:49 PM   #7
cviller is offline cviller  Denmark
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Nice!

Then we just need to adjust the gain to work nicely with F4...

I think NP already suggested 2sk389 (or matched 2sk170).
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Old 8th March 2007, 07:51 PM   #8
Zen Mod is offline Zen Mod  Serbia
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simplified enough?
even if I delete degenerative resistors randomly
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Old 8th March 2007, 08:12 PM   #9
Vix is offline Vix  Yugoslavia
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Quote:
Originally posted by Zen Mod
simplified enough?
even if I delete degenerative resistors randomly



Almost. I wanted to use resistors instead of CCS. Just keep the gain Jfets. How could we call this circuit. Bride of F4?
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Old 8th March 2007, 08:53 PM   #10
Zen Mod is offline Zen Mod  Serbia
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Quote:
Originally posted by Vix





Almost. I wanted to use resistors instead of CCS. Just keep the gain Jfets. How could we call this circuit. Bride of F4?

really depends on your power needs with F4.
if you need smaller swing,then resistors are good ;
for bigger swing you need CCSes and even higher PS voltages......and then even cascoding of jfets.

B200 still?
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