Onkyo TX-SA806 Service Manual page 146

OPERATION CHECK-2
SPEAKER PROTECT-2 (SPEAKER OUT CURRENT DETECTION)
[When]
1. Exchange power transistors (Q6050 - 6056, Q6060 - 6066).
2. Exchange amplifier PC board ass'y (NAAMP-9477, NACLA-9493).
[Procedure]
<Note>
No input.
Do not check two or more channels at the same time.
Do not connect a dummy load to speaker terminals longer than 2 seconds.
1. Press and hold down CD button, then press STANDBY/ON button while the unit is powered ON.
" Test - _ " is displayed only for 5 seconds.
Te s t - _
2. Press GAME/TV button, while " Test - _ " is displayed.
The unit will be in the state of " Test-4-00 ".
Te s t - 4 - 0 0
+
3. Repeatedly press TONE
Te s t - 4 - 3 6
4. Connect the dummy load of 3 ohms to the Front L ch speaker terminals.
At this time, confirm that the speaker relay is not turned off.
Te s t - 4 - 3 6
5. Connect the dummy load of 1 ohm to the Front L ch speaker terminals.
At this time, confirm that the speaker relay is turned off and " Protect " is displayed.
P r o te c t
Disconnect the dummy load immediately after checking the display of " Protect ".
Te s t - 4 - 3 6
6. Check other channels according to the same procedures as 4 and 5.
Front R, Center, Surround L, Surround R, Surround Back L, Surround R
7. Press STANDBY/ON button to finish.
Blinks
button until " Test-4-36 " is displayed. DSP outputs the pulse signal to all channels. Refer to Fig-1.
C l e a r
Fig-1 Current detection test signal
2 msec 2 msec
20 msec
Turn off
DSP output max.
DSP output max.
TX-SR806/SA806