3M SST, Manual

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SST Transport and Burster Mechanism Manual 75-0302-1450-8, Version 1 Ch. 6 Performing Field Repairs • 57
Replacing the PCB-2 Board
The PCB-2 Board houses the two source lights for the LEDs for the photo sensors. The PCB-2
Board also contains the flux detector circuitry (HP-1 only). When an object is inserted into the
ticket throat, the flux detector senses the presence of magnetic flux, which notes the orientation of
the object and verifies that it has some magnetic data on it. It passes this information to the CPU
Board. If the object has magnetic data encoded on it, the CPU Board signals the SST/HP-4 Trans-
port to accept it. If the flux detector is not working properly, you may need to replace the PCB-2
Board by completing the following steps:
1. Open the cabinet of the device in which the SST/HP-4 Transport resides.
2. Back out any tickets, if applicable, from the SST/HP-4 Transport by using the green but-
ton on the CPU Board.
3. Disconnect the power to the SST/HP-4 Transport.
Warning! Disconnect power before removing the SST/HP-4 Transport. If you do not dis-
connect power, you may damage the unit or severe personal injury may occur.
4. Remove the SST/HP-4 Transport. Close the cabinet.
Note: Do not carry the SST/HP-4 Transport by the Print Head. Carrying it by the Print Head may
bend the bracket and cause printing problems. Always carry the SST/HP-4 Transport from
the bottom.
5. Turn the SST/HP-4 Transport on its side.
6. Remove the Appliance Base.
7. Remove the 10-pin cable connecting the PCB-2 Board to the PCB-3 Board, from the PCB-
2 Board side.
8. Unplug the single track maghead, shown in Figure 6.6 (HP-1 only).
9. Remove the two M3 x 16 Phillips screws from the PCB-2 Board. Figure 6.6 shows the
location of the screws.