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MDS 9810 Installation and Operation Guide
MDS 05-3301A01, Rev. C
4.5 “Single-Radio” Repeater—Alternative Method
A single MDS x810 transceiver may be used to form a repeater station
to extend the range of a system. The general repeater principles dis-
cussed in Section 4.4 apply to single-radio repeaters—why repeaters are
used, geographic site considerations, etc. However, there are some
important differences in single-radio repeater systems:
•
Only one transceiver is used at the repeater site.
•
The transceiver’s TXD & RXD pins must be tied together (DB-25).
•
There may be considerable delay through the repeater, because the
radio buffers (stores) incoming data and retransmits it a short time
later.
The paragraphs that follow contain specific requirements for
single-radio repeater systems.
Interface Wiring
A single-radio repeater is formed by connecting TXD (Pin 2) and RXD
(Pin 3) on the
DATA INTERFACE
connector together as shown in
Figure 20.
Invisible place holder
Figure 20. Data Interface Cable Wiring for Single-Radio Repeater
Software Programming (TDD Command)
As with other repeater systems, the network must be configured for
TDD operation by programming the master radio with
TDD ON
. This
places the
DATA INTERFACE
port in time division duplex (sometimes
called “simulated full-duplex”) mode.
Although a single radio can never actually transmit and receive RF data
at the same time, the
TDD ON
command enables the radio to simulate
full-duplex at the data port, by designating alternate channel hops as
transmit or receive hops, and buffering data when transmission is not
permitted.
DB-25
DATA INTERFACE
CONNECTOR
2
3
TXD
RXD
Pins 2 & 3
Connected Together
for Single-Radio Repeater
