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OPERATION CHECK-1
DC VOLTAGE DETECTION PROTECTORS
CURRENT DETECTION PROTECTORS
TX-SR402/8240/HT-R420
1. Set the unit to test mode
"
Test-1-00
"
.
1-1. Press and the hold down the CD button , then press the STANDBY/ON button when the unit is Power ON.
1-2. Press the DVD button, while the display of "Test - _" has come out.
Unit will be in the state of "
Test-1-00
".
2. Apply DC voltage (+1.5 to +3V) to
MULTI CHANNEL (FL, FR, SL, SR, C, SW)
terminal, each channel.
3. Check that "protect" is display come out.
4. Apply DC voltage (-1.5 to -3V) to
MULTI CHANNEL (FL, FR, SL, SR, C, SW)
terminal, each channel.
5. Check that "protect" is display come out.
6. Press the STANDBY/ON button.
[NOTE1]
Limit time to apply voltage is 0.5 - 1.0 seconds each channel.
When protection operation does not occur at once, try several times.
[NOTE2]
Don't connect speakers or any load. Don't short speaker terminals.
[NOTE]
In the state of testmode"
Test-4-29
", the pulse waveform for checking from speaker terminal outputs automatically.
Therefore, oscllator is unnecessary.
T e s t - _
T e s t - 1 - 0 0
C l e a r
Disappears
1. Set the unit to test mode
"
Test-4-29
"
1-1. Press and the hold down the CD button , then press the STANDBY/ON button when the unit is Power ON.
1-2. Press the VIDEO3 button, while the display of "Test - _" has come out.
Unit will be in the state of "
Test-4-00
".
1-3. Repeat and press SPEAKERS B until the display of "
Test-4-29
" comes out.
2. Connect the lord resister (3ohms) to the speaker terminals.
3. Check the not displayed
"PROTECT"
and speaker relays
not
turn OFF.
4. Check the each speaker terminals.
5. Connect the lord resister (1.5ohms) to the speaker terminals.
6. Check the displayed
"
PROTECT
"
and speaker relays turn OFF immediately.
7. Check the each speaker terminals.
6. Press the STANDBY/ON button.
T e s t - _
T e s t - 4 - 0 0
T e s t - 4 - 2 9
C l e a r
Disappears