Adjustment And Confirmation Procedures - Onkyo TX-DS898 Service Manual

A

ADJUSTMENT AND CONFIRMATION PROCEDURES

Idling current adjustment
Before Idling adjustment, turn the trimming resistors R6040 to R6046 to counter clockwise.
Connect the DC voltmeter to sockets P6080 to P6086.
1
After turn POWER to ON, adjust the trimming resistors R6040, R6041 and R6042 so that the reading of
voltmeter becomes 7.0 mV. (Front and center channels)
Adjust the trimming resistors R6043, R6044, R6045 and R6046 so that the reading of
voltmeter becomes 5.0 mV. (Surround and surround back channels)
After adjustment, attach the top cover.
Confirm the voltage of points above after about five minutes.
Front and center channels
When less than 9.0 mV, readjust the resistors above so that the voltage becomes 9.0 mV.
When 9.0 mV to 11.0 mV, you are not necessary to adjust.
When more than 11.0 mV, readjust the resistors above so that the voltage becomes 11.0 mV.
Surround and surround back channels
When less than 6.0 mV, readjust the resistors above so that the voltage becomes 6.0 mV.
When 6.0 mV to 8.0 mV, you are not necessary to adjust.
2
When more than 8.0 mV, readjust the resistors above so that the voltage becomes 8.0 mV.
Note: No load and No signal
3
P6083
+ID
-ID
SL ch.
4
Confirmation of protection circuit
1. Confirmation of operation of speaker relay
Confirm that the speaker relays turn ON approximate. 5 seconds after the power switch is turned ON.
Confirm that the speaker relays turn OFF immediately after the power switch is turned OFF.
2. Confirmation of DC detection circuit
Press and hold down CD button, then press STANDBY/ON and DISPLAY buttons to set the unit to
"TEST-1" mode.
After "TEST-1" on the FL tube light on, press VIDEO 1 button to set the unit to "TEST-1-00".
Apply DC 1.5 to 3V to MULTI CHANNEL INPUT terminal with no load.
Confirm that the speaker relay turns OFF.
5
Apply DC -1.5 to -3V to MULTI CHANNEL INPUT terminal with no load.
Confirm that the speaker relay turns OFF.
Caution: Don't apply DC voltage more than 1 sec..
B
L ch.
- I D
+ I D
R6040 P6080
R6043 P6084 R6044
+ID
-ID
SR ch.
C
R ch.
- I D
+ I D
R6041 P6081 R6042
P6085 R6045 P6086
+ID +ID
-ID -ID
SBL ch. SBR ch.
C ch.
- I D
+ I D
P6082
R6046
NAAF-7250
TX-DS898
D