What is the current through the PC817 pin 4 and 3? about 0.5mA?
On datasheet, it seems to depend.
they are here ...... D3 being in same place , still , working same duty in both Babelfish M25 and SissySIT - preventing lower gate to wrap around output node in positive clipping for more than one diode drop voltage
in case of Babelfish M25 and M2 , D1 and D2 are doing same thing , for negative clipping - preventing upper gate to wrap around output node for more than 2 diode drop voltages
however , in SissySIT , upper gate is already bellow output node , so leaving D1 and D2 here is Big NoNo , they will conduct pronto , so bye with any function of ....anything
so ,fro SissySIT, toss out D1 and D2 , introduce D4 and D5 , and they'll prevent upper gate to wrap around neg rail for more than 2 diode drop voltages
simple , isn't it ?
also observe difference in orientation of ZD1, SissySIT vs. Babelfish M25
in case of Babelfish M25 and M2 , D1 and D2 are doing same thing , for negative clipping - preventing upper gate to wrap around output node for more than 2 diode drop voltages
however , in SissySIT , upper gate is already bellow output node , so leaving D1 and D2 here is Big NoNo , they will conduct pronto , so bye with any function of ....anything
so ,fro SissySIT, toss out D1 and D2 , introduce D4 and D5 , and they'll prevent upper gate to wrap around neg rail for more than 2 diode drop voltages
simple , isn't it ?
also observe difference in orientation of ZD1, SissySIT vs. Babelfish M25
it's simple ....... just imagine what's happening when dumb or drunk operator turns preamp volume control few full circles , then some
input buffer goes Berserk , autoformer is even multiplying that berserk , while gates of output devices are trying to reach both roof and cellar ..........
in same time , PSU rails are much lower than roof and much higher than cellar , and sources are simply unable to leave window between two rails
so , something must be there to prevent gates to go out of building
input buffer goes Berserk , autoformer is even multiplying that berserk , while gates of output devices are trying to reach both roof and cellar ..........
in same time , PSU rails are much lower than roof and much higher than cellar , and sources are simply unable to leave window between two rails
so , something must be there to prevent gates to go out of building
ZM, how low could one let go Iq, lets say not having Berserker but more a Sissy SissySIT? Have very sensitive speakers (100db) and can't radiate 170 Watt in my living room environment BUT I am highly interested in the SIT sound. Any chance for that or is ist the wrong amp to do such a thing?
Cheers
Ernst
Cheers
Ernst
according to your table , no go ..... no certain voltage window to squeeze opto bjt in
gate to gate is different , so other solutions already shown in Most Greedy Boy, of them all... or (there is no) DEFiSIT of Papa's Koans are viable
of course , one can be sure only after testing exact 2SK182 specimens under prescribed conditions - rails 22 to 25V and Iq 1A8 to 2A
gate to gate is different , so other solutions already shown in Most Greedy Boy, of them all... or (there is no) DEFiSIT of Papa's Koans are viable
of course , one can be sure only after testing exact 2SK182 specimens under prescribed conditions - rails 22 to 25V and Iq 1A8 to 2A
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