Chapter Three
Operation
Page
23
Module A, B and C are configured as transparent repeaters. Module A is configured with group
addresses 1 & 2, module B with group addresses 2 & 3 and module C with group addresses 3 &
4.
Module S and T are configured with group address 1 (only one group address as it is not
configured as a repeater). When S transmits a message, T and A will receive it and output the
data. If module X can hear the message, it will not output it as module X is configured with
group address 2.
Repeater A will re-transmit the radio message, but on group address 2. Module S and T will
receive the re-transmitted message, but will not output the message as the group address is now
wrong. Module X will receive the message and will output the message as the group address is
now correct.
Repeater B will also receive the re-transmitted message from A, and will output the data as well
as re-transmit on group address 3.
The only other module which is also on group address 3 is repeater C. It will accept the message
and re-transmit it on group address 4 - to module Z.
Note that when a message is transmitted from a remote module, the repeaters will only transmit
a message in one direction. For example :
When X transmits a message, repeater A will receive the message on group address 2. Repeater
A will not output the data as the group address is not the repeater’s first group address. Repeater
A will re-transmit on group address 1 to modules S and T. But repeater B will not accept the re-
transmitted message on group address 1.
If repeater B is able to hear the original message from module X (on group address 2), then it
will re-transmit it on. But if it cannot, then the message will not be transmitted on to module Z.
A
B
C
G ro u p Ad d re s s
F irs t
1
2
3
S e c o n d
2
3
4
S
T
X
Z
R e p e a te rs
Re m o te
M o d u le s
G ro u p Ad d re s s
1
2
4