Troubleshooting - Sony DSC-S75 Training Manual

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The lines are monitored by Q017A and B, and Q001. Each of these transistors also has a positive reference
voltage applied to it.
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In normal operation, the base of the transistors is approximately 0V.
•
The transistors will turn on if the negative voltages drops to the point that the transistor base rises to +1.3V.
This puts the SCP line LOW and shuts down the power supply

Troubleshooting

The power supply circuit should be checked in the following order:
1. BT-006 board
2. FR-181 board
3. Short circuit protection.
Checking BT-006 Board
Since "live" troubleshooting is limited, the technician must make a determination if the problem is on the BT-006
or the FR-181 board.
The BT-006 board is easier to troubleshoot in "passive mode" – with the unit off – and should be checked first. If
the BT-006 board is ok, then the FR-181 board should be checked.
Checking Fuses
Fuses should be checked first. Their locations are
shown in Figure 15-3. See caution on the following
page "Discharging Storage Capacitors".
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Fuses are located on the 'back' side of the board
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Fuses look like chip resistors
•
If a fuse is open, check the circuits that it feeds
on the FR-181 board for shorts.
Removing BT-006 board
See next paragraph for caution before removing the
BT-006 board. This board is easy to remove. With
the camera back off:
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Remove the FR-181 board (held by two screws).
•
Remove the battery holder.
•
Remove the BT-006 board.
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15. DSC-F707 Power Supply
Figure 15-3