I bought this amp used about 1984 and it's served me well all these years. Still works perfect but I thought I'd treat it to some bench TLC.
After blowing out the dust it went to the test bench where i warmed it up for 20 minutes boosting a 1kHz input to 50watts output.
I tweaked the offset to under 1mV.
Then I checked the bias of each channel by removing the B+ fuse and contacting a digital ammeter in its place. They were in the 300-350mA range at idle (zero signal), into 8ohm loads.
I don't know what the bias should be, and this amp has the reputation of running pretty warm--possibly due to a rather highish bias setting.
Anyone KNOW? SWAG not needed--I can guess without any help. 😉
After blowing out the dust it went to the test bench where i warmed it up for 20 minutes boosting a 1kHz input to 50watts output.
I tweaked the offset to under 1mV.
Then I checked the bias of each channel by removing the B+ fuse and contacting a digital ammeter in its place. They were in the 300-350mA range at idle (zero signal), into 8ohm loads.
I don't know what the bias should be, and this amp has the reputation of running pretty warm--possibly due to a rather highish bias setting.
Anyone KNOW? SWAG not needed--I can guess without any help. 😉
ماژول پری آمپلی فایر و تن کنترا استریو کاملا حرفه ای
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Nice answer hassan4119
Can you see what type of MosFets are in the heatsinks ?
Found a post in another forum where the OP measured +/-280 in one channel and +/-330mA in the other and since you measured in the range of 300/350mA I would set it at 300mA and go from there keeping an eye in the temperature.
Just my 2 cents no expert here.
Good luck
Can you see what type of MosFets are in the heatsinks ?
Found a post in another forum where the OP measured +/-280 in one channel and +/-330mA in the other and since you measured in the range of 300/350mA I would set it at 300mA and go from there keeping an eye in the temperature.
Just my 2 cents no expert here.
Good luck
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