TROUBLESHOOTING B GUIDE
11
B
Finish
Rear panel led show green?
YES
NO
led turn off?
Rear panel led show red?
NO
YES
Check D500 U505 circuit,
YES
Check Q500 Q502 Q508 circuit
Change NC400 OEM BOARD
Apply 1khz sinew ave to DUT
Amplifier output correct?
YES
NO
INC INH signal correct?
YES
Change NC400 OEM BOARD
check+/-14.5V,5V Right?
NO
checkQ505 Q506 Circuit
NO
change AMP board
YES
checkU500 U501 U502 U503 Circuit
change AMP board
checkQ503 Q504 Circuit
Summary of Contents for M27
Page 1: ...NAD SERVICE MANUAL M27 SEVEN CHANEL M27 SEVEN CHANEL AMPLIFIER AMPLIFIER...
Page 6: ...6...
Page 26: ...1 MCU BOARD 26 PCB LAYOUT TOP Layer Bottom Layer...
Page 27: ...27 2 REGULATED SUPPLY BOARD Top Layer Bottom Layer...
Page 28: ...28 3 AMP BOARD Top Layer Bottom Layer...
Page 29: ...29 4 NC400 OEM BOARD Bottom Layer Top Layer...
Page 31: ...31 8 SMPS BOARD Bottom Layer Top Layer...
Page 32: ...32 9 SMPS STB BOARD 1 2 Bottom Layer Top Layer...
Page 33: ...33 9 SMPS STB BOARD 2 2 Bottom Layer Top Layer...