Hello all, This amp has been a journey. I finally got all matching good toshiba transistors for my alpine 3545 and installed. Going to do the voltage and idle current adjustments from the service manual and wanted to know if this is done cold or warm. The values rise at the test points as it gets warmer so I want to do it the right way. Any info is appreciated. Thanks alot
If the bias transistor is in good thermal contact with the output transistors and all of the outputs are clamped to the heatsink, the bias current should not vary much with a change in temperature. If it does, that would tend to indicate that the outputs are not the same as the originals. This is common with counterfeit parts.
Honestly everything fluctuates as it warms up. The main voltage set to 104v and the idle current 4mv on both sides. The untouched channel and the repaired channel. Not by alot but when I set it cold to 4mv it will move to 5mv after a minute. Wasnt sure if its normal but both the original and replaced channel do it. That's why I didnt know I'f it was adjusted at first turn on or cold. Thanks
Operate all pots and switches through their entire range to see if it makes a difference.
These amps can be very difficult to get right. There have been a lot of leaky caps on the vertical board on the ones I've repaired which can cause various problems. There have also been bad connections on some of the jumpers from one side of the board to the other.
These amps can be very difficult to get right. There have been a lot of leaky caps on the vertical board on the ones I've repaired which can cause various problems. There have also been bad connections on some of the jumpers from one side of the board to the other.
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