Hey to everyone.
I burned all my mosfets when putting amp on heatsink without isolating tape. So i replaced my irfp244 mosfets and turned on the amp, and when i try to play some music the sound is not like a class amp. So i desoldered my irfp9610 and measured they are also dead. I solder new ones and try to play music again and its a little better than before but not good at all. And the mosfets irfp244 are cold as ice after 20min of running time. Maybe any ideas what can be wrong?
I burned all my mosfets when putting amp on heatsink without isolating tape. So i replaced my irfp244 mosfets and turned on the amp, and when i try to play some music the sound is not like a class amp. So i desoldered my irfp9610 and measured they are also dead. I solder new ones and try to play music again and its a little better than before but not good at all. And the mosfets irfp244 are cold as ice after 20min of running time. Maybe any ideas what can be wrong?
Schematic is the same like here PASS LABS ALEPH-5 - Class-A DIY amplifier schematic & PCB
I measured the Voltages on all 1ohm rezistors everywhere is almost 0V. Also measure on MPSA18 between E and C also almost 0V.
I measured the Voltages on all 1ohm rezistors everywhere is almost 0V. Also measure on MPSA18 between E and C also almost 0V.
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it's hard communicating without parts nomenclature
ok, schm enclosed
what's voltage across 9V1 on top , in upper IRF9610 gate?
what's voltage across 220R on top , in upper IRF9610 source?
what's voltage across 390R on bottom , in left IRF9610 drain?
what's DC offset on output?
inputs grounded, output not loaded
ok, schm enclosed
what's voltage across 9V1 on top , in upper IRF9610 gate?
what's voltage across 220R on top , in upper IRF9610 source?
what's voltage across 390R on bottom , in left IRF9610 drain?
what's DC offset on output?
inputs grounded, output not loaded
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I speak with the guy who sell me that diy amp kit and asked about matched parts. he write me (in that case you will not have sound problems... it means that some mosfet will be more heat than others. Your mosfet do not heat at all and sound is bad so problem is something other. Try to change white cap 680pf . It is good , but try to use any from 680 to 1nf).
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