Tail-End Links; Interface Wiring - Microwave Data Systems MDS 9810 Installation And Operation Manual

Interface Wiring

Antennas
Full-Duplex
Configuration
MDS 05-3301A01, Rev. C
frequencies (
MODE R-M
grammed as a master (
Pin 2 (TXD) of the master radio must be connected to Pin 3 (RXD)
of the other radio (the one programmed as
interface cable. This allows the signals received by the
radio to be re-transmitted by the master. The signal ground leads
(Pin 7) must also be connected to each other.
RXD
TXD
GND
Figure 17. Data Interface Cable Wiring
for Peer-to-Peer Systems with Repeater Assistance
Two omnidirectional antennas are required at peer-to-peer repeater
stations—one for each radio. It is important to minimize coupling
between these antennas. The necessary isolation can be achieved by
vertical separation. In this arrangement, one antenna is mounted
directly over the other, separated by at least 10 feet (3.2 Meters).
This takes advantage of the minimal radiation exhibited by verti-
cally polarized antennas directly above and below one another.
The paragraphs above discuss the requirements for a basic Repeater
Assisted Peer-to-Peer system. If a full-duplex system is required
(with the SCADA host computer located at the repeater), additional
considerations apply. If you are constructing this type of system,
contact the factory and request a copy of Application Bulletin
97002. The bulletin can also be found at www.microwavedata.com.

4.3 Tail-End Links

A tail-end link is established by connecting the radio "back-to-back"
with another radio such as a licensed MDS 2300/4300 series transceiver.
This can be used to link an outlying remote site into the rest of an MAS
network. Here are some specific requirements for tail-end link systems:
Interface Wiring
The connection between the two radios in a tail-end link system
must be made as shown in Figure 18.
MDS 9810 Installation and Operation Guide
command, Page 41), and the other pro-
command).
MODE M
Invisible place holder
DB-25 DB-25
3 2
2 3
7 7
) using a local
MODE R-M
MODE R-M
TXD
RXD
GND
21