Or just use an independent bias string for the top output FET; maybe a CCS diode feeding a resistor (R1) to set a voltage, then a sizeable resistance (R2) feeding the gate stopper resistor (R3). From the junction of resistors R2 and R3 connect a capacitor to the amp output node. In essence very similar to what the tube guys do on a hybrid 'mu follower'.
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Circlotron demystified
It seems to me that John Broskie's article "Cars, Planes, and Circlotrons" provides the keys to understanding the circlotron because of its behavioral equilavence to the totom pole topology. Unless I am totally missing something, there isn't any "Quantum weirdness" here.
The way to understand a circlotron is to meditate on it until
you reach enlightenment. When you understand the
circlotron you can move on to quantum mechanics.
not kidding.
It seems to me that John Broskie's article "Cars, Planes, and Circlotrons" provides the keys to understanding the circlotron because of its behavioral equilavence to the totom pole topology. Unless I am totally missing something, there isn't any "Quantum weirdness" here.
I am not Nelson, but I retrofited my F2, It's Q1.
Additionally - From Nelson Pass
The F2's that I have updated with the JFETs need the
following changes:
R6 = 47k
C1 = 10 uF
Z1 removed
The potentiometer must be re-adjusted for minimum
distortion at 4.5 watts (symmetric clipping) and readjusted
after an hour..
I would guess it would with plenty of sinking, but I would think a current source of IRFP240 would not. The IRFP240's are recommended to run less than 65c. The math escapes me on what the F2-F2j is doing for output. I think it's 65watts total per side, so that's roughly 33 watts a device? Someone else surely has a more precise answer.
24w per chanelI would guess it would with plenty of sinking, but I would think a current source of IRFP240 would not. The IRFP240's are recommended to run less than 65c. The math escapes me on what the F2-F2j is doing for output. I think it's 65watts total per side, so that's roughly 33 watts a device? Someone else surely has a more precise answer.
but irfp240 only for ED
for curent source i use 2sk1530
Some high praise here for XA100.5 and FirstWatt J2 from Tone Audio.
http://www.tonepublications.com/MAGPDF/TA_030.pdf
Check out page 158. I cannot copy text from it, must be protected.
Anyways, My first half-decent speakers were a gifted pair of Maggie MG-I's, restored by Magnepan.
http://www.tonepublications.com/MAGPDF/TA_030.pdf
Check out page 158. I cannot copy text from it, must be protected.
Anyways, My first half-decent speakers were a gifted pair of Maggie MG-I's, restored by Magnepan.
