Multiplexer Module (TX2A/TX4A)
18 November 1996
MUX-6
2. Product Function
2.1 Description
The 2 Channel Multiplexer Module allows the use of 2 transmit/receive (TX/RX) antennas with
one RF Module and the 4 Channel Multiplexer Module allows the use of up to 4 transmit/receive
(TX/RX) antennas with one RF Module.
The Multiplexer is connected between an RF Module and the TX/RX antennas. All antennas can
be disabled by removing one jumper.
The supply voltages and channel selection signals are connected via a 4-pin connector.
The connection to the RF Module and to the antennas is made via two screw block terminals.
The channel select input signals, connected to a data processing unit (for example: TIRIS Series
2000 Control Module, or a customer designed control unit), are Low Power Schottky TTL and
HCMOS Logic compatible.
The Multiplexer includes circuitry to reduce crosstalk of transmit function.
There are four connectors on the Multiplexer in total, these are:
J1
which is used to connect the supply voltage and channel select signals
J3
which is used to connect up to 4 TX/RX antennas
J4
the antenna resonator connector, which is used to connect the Multiplexer board to
the antenna terminals of the RF Module
J6
which can be used to connect the Multiplexer ground to earth
The Multiplexer can be mounted by means of four M3 mounting bolts on the under-side of the
module.
A layout of the Multiplexer viewed from the top is shown in figure 1 (the parts in dotted lines are
not mounted for the Module RI-MOD-TX2A). A block schematic of the Multiplexer is shown in
figure 2. The Multiplexer is described in the following section.
