Instruction manual, SPT and MPT 31x series transponders

Maintenance
3 Mount the new circuit board and tighten the locking
devices. Take care not to over-tighten the locks.
Rx-amplifier matching board
To replace one of these circuit boards, follow the procedure
below:
1 Open the transponder.
2 Remove the soldering at the connections. Remember to
mark the wires.
3 Unscrew the four screws holding the board. The
appropriate board can now be removed from the chassis.
4 Assemble the transponder.
How to replace the transducer
The transducer is a sealed unit and can not be opened. If the unit
is not working, the whole unit must be replaced. Separate
procedures are provided for:
Aluminium transponders
Stainless steel transponders
Aluminium transponders
1 Open the transponder.
2 Remove the transducer cage. The cage is bolted to the
“cone”, which is screwed onto the top end cap.
3 Remove the soldering at the connections Tp1 and Tp 2 on
the Rx amplifier matching board (the Tp1 and Tp2 are
clearly marked). Remember to mark the wires.
4 Remove the electronic chassis (8 fixing screws).
5 Remove the transducer securing screws. This is done from
the inside of the top end cap.
6 Assembly is basically the reverse of opening
Stainless steel transponders
1 Open the transponder.
2 Remove the transducer cage (if fitted).
3 Remove the soldering at the connections Tp1 and Tp 2 on
the Rx amplifier matching board (the Tp1 and Tp2 are
clearly marked).
160820/O 77