Marantz SA12 - Trouble Shooting AV Board; Audio Part

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5.7 Trouble shooting AV Board
Testing of A/V board can be done using diagnostic software “Player script”.
Mono board is used to generate a sound with the sound tests PINKNOISE ON and SINE ON.
A VIDEO signal is generated with COLOUR-B ON.
Functional control of scart switching is also possible.
Diagnostic Software
DAC UDA1328T
& FILTERING
POWER SUPPLY?
Check DAC IC 7401
Check C2455, C2459, C2461, C2464.
NP0 TYPE?
Check OPAMPS 7403, 7408.
Check ELCO'S 2456, 2462, 2475
Check OPAMPS 7403, 7408.
Check resistors 3455, 3459, 3464, 3448, 3451, 3453
3479, 3475.
Check OPAMPS 7403, 7408.
KILL: -8V DURING PLAY?
Check for analog signal at outputs of DAC IC 7401: pin
1,2,4,5,28,29,31,32 (testpoint 14).
Check DAC IC 7401
Check VREFA on pin 30 of DAC 7401: 1.65V?
Check testpoints 7, 8, 9, 10, 12, 13.
Check flex connection to mono board
Check mono board
Check supply voltages 3V3(IC 7400), +8Vaud(IC 7304),
-8Vstby(R3615), +12Vstby(T7333).
Check flex connection to mono board.
NO
YES
PCM_OUT[0:2]
LRCLK, SCLK
PCM_CLK
?
NO
YES
NO
YES
AUDIO
CINCH OUTPUTS
Testpoint 15?
NO
YES
AUDIO
AT OUTPUTS
OF DAC 7401
?
NO
YES
LEVEL OK?
YES
N0
DISTORTION?
To put set in “Player script”, press keys
STOP+OPEN/CLOSE simultaneously and switch player on.
Proceed until display shows .
Press
PLAY to execute.
During this test, an audio pink noise signal will be
sent to the audio cinches and the audio outputs of the
scarts..
AUDIO PART
" PINKNOISE ON"
DAC & FILTERING
OK