Hello, I have a "threshold s200" which had a power transistor HS "MJ15022"
I have completed the replacement by a "mj15022G"
The amplifier works again but I would set the bias, because the repaired heater side a bit compared to the other.
If anyone knows the procedure?
thank you in advance
I have completed the replacement by a "mj15022G"
The amplifier works again but I would set the bias, because the repaired heater side a bit compared to the other.
If anyone knows the procedure?
thank you in advance
search here , plenty of that
also , see here : Nelson Pass related | Zen Mod Blog
also , see here : Nelson Pass related | Zen Mod Blog
ok thank you, but the s200 model must be inserted on the meter but the positive or? the board on the pdf file is not the same as on the s200.
An externally hosted image should be here but it was not working when we last tested it.
........
do you know which trimpot is for setting Iq , in your amplifier ?
Hello, here are the photos.
Can you tell me where I have to make the measurement with the multimeter?
I replaced the trimpot with a better (SLAB) and especially more accessible for adjustment !!
regards
gilles
Can you tell me where I have to make the measurement with the multimeter?
I replaced the trimpot with a better (SLAB) and especially more accessible for adjustment !!
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
regards
gilles
well , you being Frenchy , moi being Serb ...... writing on Engrish ...... there surely must be some hiccup
you have non-repaired side , with proper temperature on heatsink;
measure voltage across one emiter resistor (big 1R thingie , any of them) and take that as reference ;
move voltmeter on other side emiter resistor (cold channel) , and re-bias it , to have approx. same voltage across resitor and similar temp on heatsink ..... as other (untouched) channel
if both are well under desired heatsink temperature , re-bias them both
you have non-repaired side , with proper temperature on heatsink;
measure voltage across one emiter resistor (big 1R thingie , any of them) and take that as reference ;
move voltmeter on other side emiter resistor (cold channel) , and re-bias it , to have approx. same voltage across resitor and similar temp on heatsink ..... as other (untouched) channel
if both are well under desired heatsink temperature , re-bias them both
something's wrong - 180mV across 1 Ohm , for 45C
and 320mV for 22C
be sure that you're checking same positioned resistors , pcbs are the same .......
recheck other 1R resistors , that way you'll also know is some output transistor gone Dodo
if these resistors are looking good ( no cracks ) and measure good (resistance) , there is no need to change them
and 320mV for 22C
be sure that you're checking same positioned resistors , pcbs are the same .......
recheck other 1R resistors , that way you'll also know is some output transistor gone Dodo
if these resistors are looking good ( no cracks ) and measure good (resistance) , there is no need to change them
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