Denon AVR-S740H Service Manual

4.2. Power AMP (AMP PCB)
No audio output.
Protection is activated.
Is the power transistor open or short circuited?
2SB1560 / 2SD2390
Is the emitter resistor of the power transistor
open?
0.47 Ω
Is the base resistor of the power transistor open?
4.7 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 current.
Replace the power transistor.
Replace the transistor.
Replace the resistor.
Replace the emitter resistor.
Replace the base resistor.
Replace the trimmer potentiometers.
When using the protection pass mode, do not connect speakers to the speaker terminals.
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
Check the CPU.
4.3. Analog audio
No audio output.
Is a voltage of ± 12V supplied to DIGITAL PCB
[CN823]?
Is there an audio signal in DIGITAL PCB [CN822]?
Reconnect the connectors correctly.
If the malfunctioning channel and function can be identied, check the corresponding signal path.
Repair the ± 12V power supply.
Repair the power amplier.
Is the serial data for electronic volume sent to the
[IC822] of DIGITAL PCB?
NO
YES
NO
YES
NO
YES
Before Servicing
This Unit
Electrical Mechanical Repair Information Updating
76

Denon AVR-S740H Specifications

General

Channels	7.2
Power Output per Channel	75 W (8 Ohms, 20 Hz - 20 kHz, 0.08% THD)
HDMI Inputs	6
HDMI Outputs	1
Dolby Atmos	Yes
DTS:X	Yes
Bluetooth	Yes
Wi-Fi	Yes
HEOS Multi-room	Yes
4K Ultra HD Pass-through	Yes
Power Output per Channel (6 Ohms)	110 W (6 Ohms, 1 kHz, 0.7% THD)
4K/Ultra HD Upscaling	Yes
Phono Input	Yes
Dolby Support	Dolby Atmos, Dolby TrueHD, Dolby Surround
Auto Calibration	Audyssey MultEQ
Input Sensitivity/Impedance	200 mV / 47 kOhms
Signal-to-Noise Ratio	98 dB (IHF-A weighted, Direct mode)
Ethernet	Yes
USB Port	Yes (front)
AM/FM Tuner	Yes
Supported Audio Formats	MP3, WMA, AAC, FLAC, ALAC, WAV, DSD
HDR Support	HDR10, HLG, Dolby Vision
Wireless Audio	AirPlay 2
DTS Support	DTS:X, DTS-HD Master Audio
Zone Audio	Zone 2
Frequency Response	10 Hz - 100 kHz (+1, -3 dB, Direct Mode)
Total Harmonic Distortion	0.08% (20 Hz - 20 kHz)
Built-in DAC	192 kHz / 24-bit