Denon AVR-X3300W - Page 76

4.2. Power AMP (AMP PCB)
No audio output.
Protection is activated.
Is the power transistor open or short circuited?
2SB1647 / 2SD2560
Is the emitter resistor of the power transistor
open?
0.47 Ω
Is the base resistor of the power transistor open?
22 Ω
Is the trimmer potentiometer between the base
of the power transistor open?
1 k Ω
Are any other transistors faulty?
Are any other resistors faulty?
Turn on the power and, check that the voltage of each part is correct and that there is an idling cur-
rent.
Replace the power transistor.
Replace the transistor.
Replace the resistor.
Replace the emitter resistor.
Replace the base resistor.
Replace the trimmer potentiometers.
NO
NO
NO
NO
NO
NO
YES
Connect the connectors correctly.
Repair the HDMI PCB.
4.3. Analog audio
No audio output.
Is a voltage of ± 8 V supplied to INPUT PCB
CN4201?
Is there an audio signal in INPUT PCB CN4200?
Reconnect the connectors correctly.
If the malfunctioning channel and function can be identied, check the corresponding signal path.
Repair the ± 8 V power supply.
Repair the power amplier.
Is the connector correctly connected to the
HDMI PCB?
YES
NO
YES
YES
YES
YES
YES
YES NO
YES
NO
YES
YES
76
Caution in
servicing
Electrical Mechanical Repair Information Updating