OPERATION CHECK-1
SPEAKER PROTECT-1 (DC VOLTAGE DETECTION)
DTR-7.7
1. Press and hold down CD button, then press STANDBY/ON button while the unit is Power ON.
" Test - _ " is displayed only for 5 seconds.
2. Press VIDEO 3 button, while the characters of " Test - _ " are displayed.
The unit will be in the state of
" Test-4-00 ".
3. Repeatedly press TONE
+ button until the characters of " Test-4-21 " are displayed.
[Procedure]
<Note>
No load. No input signal.
Test - _
Test - 4-00
[When]
1. Exchange power transistors (Q6050 - Q6056, Q6060 - Q6066).
2. Exchange amplifier PC board ass'y (NAAF-8678, NAAF-8682).
Test - 4-21
Check whether the operation starts and continues automatically as follows.
Test - 4-21
Test - 4-22
Test - 4-25
Test - 4-23
Test - 4-24
Protect OK
Protect OK
Protect
Protect OK
Protect OK
Protect OK
Test - 4-35
Clear
Turn off
Front L ch
Check
If all channels are OK, the characters of
" Test - 4 - 35 "
are finally displayed.
4. Press STANDBY/ON button.
Front R ch
Check
Center ch
Check
Surround L ch
Check
Surround R ch
Check
Blinks
Test - 4-26
Protect OK
Surround Back L ch
Check
Test - 4-27
Protect OK
Surround Back R ch
Check