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Old 23rd April 2009, 07:01 PM   #1681
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variable voltage drop down to 8v, idss dipendent ,10ma to 7ma

% match max ? ie 7,6 -7,8 are ok?
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Old 23rd April 2009, 07:06 PM   #1682
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I guess you measure voltage across some resistor so to extract IDSS current information. Use simpler and see. Yes, 7.6-7.8 not great matching is OK. It is not audio, its regulator.
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Old 23rd April 2009, 07:13 PM   #1683
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probabile my stupid problem are only dmm battery , I just remenber without dmm in series ,and analog tester on v ,I dont see any drop !!!!

I will repor later, thanks a lot as always
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Old 23rd April 2009, 08:33 PM   #1684
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now work but I don't know why !!!
MiniReg problem...
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Old 24th April 2009, 02:44 AM   #1685
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I didn't really understand the problem, but could it be sudden increase in current that causes voltage drops at those points? Also, if any parts get too hot, some of the current passing properties change quite a bit.
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Old 24th April 2009, 03:31 PM   #1686
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match done not so lucky
How can be the idss difference from channel ?

A----
k6.70-k6.70

k6.84-k6.91

b----
j7.72-k7.77

j7.90-k7.90

c----- but can be better for audio
j7.91-k7.90

j8.02-k8.02

d--- but losting the up combo for audio
k8.00-k8.02

k8.08-k8.09

e----- if idss is not too higth this are the better
k8.26-k8.27

j8.38-k8.37

with one ?
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Old 24th April 2009, 04:36 PM   #1687
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All will work. Your choice.
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Old 24th April 2009, 06:31 PM   #1688
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thanks , the same for R6 mod ?

a--- for r6 mod

e--- for Q5
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Old 24th April 2009, 07:07 PM   #1689
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Yes, good choices. Remember that R6 mod at this voltage you use is going to stress the BJT if not mini sinked.
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Old 24th April 2009, 07:24 PM   #1690
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just for fun or crazy

how mix for channel balance a-- and e-- jfet ?

ie: lower a-- idss for Q5 with higth e-- idss for R6mod
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