User's Manual

MDS 05-2708A01, Rev. D MDS TransNET I&O Guide 39
For a Remote radio, under normal operation, RSSI is based on the average
signal strength of the SYNC message received in each of the eight frequency
zones. (RSSI is sampled each time a SYNC message is received.) When using
the RSSI reading to align a directional antenna, it is important to make
changes slowly so that the RSSI reading will provide meaningful results. It
will take several seconds to indicate a change in signal level. The radio stays
in RSSI mode until is pressed.
For a Master radio, under normal operation, entering the RSSI command
causes the response NOT AVAILABLE to be returned. This is because a Master
is normally receiving signals from several Remote stations and an RSSI
reading would be continually changing. The only exception is when the
SETUP command has been asserted. This disables hopping and allows
reading a “raw” RSSI signal level in real time from a Master or Remote radio.
NOTE 1: RSSI readings will not accurately indicate signals stronger than –40 dBm.
NOTE 2: RSSI works for Dependent Masters. Command displays “NOT AVAILABLE” if
the Dependent Master is not synchronized.
RTU [ON, OFF, 0-80]
Remote Terminal Unit Simulator
This command re-enables or disables the radio’s internal RTU simulator,
which runs with MDS’ proprietary polling programs (poll.exe and rsim.exe).
The internal RTU simulator is available whenever a radio has diagnostics
enabled. This command also sets the RTU address to which the radio will
respond.
The internal RTU can be used for testing system payload data or pseudo bit
error rate (BER) testing. It can be helpful in isolating a problem to either the
external RTU or the radio. The default RTU setting is OFF.
RX [xxxx]
Radio Receive Test Frequency
This command sets or displays the test receive frequency used in place of
hopping when the radio is in SETUP mode. The test receive frequency can be
reprogrammed to any value between 902.200 MHz and 927.800 MHz, inclu-
sive. The factory default setting is 915.000 MHz.
RXD [0–235] / [ON/OFF]
RXD Delay
Used to set a delay, in milliseconds, of RXD data to emulate a seamless mode
with much lower latency in applications where retries are not required. Use a
delay of twice the value of the HOPTIME period (See page 34).
Entering a RXD ON (0 ms default) or RXD XX will enable the function.
Entering
RXD OFF will disable the function and erase any stored value.
ENTER