This is from the qm 75.6 mx service manual. The final idle current is for 6 channels. Yours will be a bit less.
The procedure must be effected without any input signal and any load!
The PCB must be mounted on heatsink!
1. With the amplifier without any connection rotate anticlockwise each trimmer to the end
point.
2. Connect the power supply to the amplifier. The input voltage must be 13,0V. You must have
a voltmeter and amperometer to input supply.
3. Switch on the amplifier using the remote input.
4. Wait about 20 sec then read the value of idle current using the amperometer. The standard
value is 800 mA
5. Rotate clockwise the trimmers, one trimmer at time, to increase the iddle current of 50 mA
each trimmer. This procedure must be effected carefully, a fast rotation shall cause an
amplifier instability causing a faulty
6 . At the end of the procedure the idle current must be 1,1 A
The procedure must be effected without any input signal and any load!
The PCB must be mounted on heatsink!
1. With the amplifier without any connection rotate anticlockwise each trimmer to the end
point.
2. Connect the power supply to the amplifier. The input voltage must be 13,0V. You must have
a voltmeter and amperometer to input supply.
3. Switch on the amplifier using the remote input.
4. Wait about 20 sec then read the value of idle current using the amperometer. The standard
value is 800 mA
5. Rotate clockwise the trimmers, one trimmer at time, to increase the iddle current of 50 mA
each trimmer. This procedure must be effected carefully, a fast rotation shall cause an
amplifier instability causing a faulty
6 . At the end of the procedure the idle current must be 1,1 A
