Microwave Data Systems MDS 4310, Installation, Operation & Field Maintenance

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3-10 PROGRAMMING AND DIAGNOSTICS MDS 05-2415A01, Rev. A
DIAGNOSTIC EXAMPLES
RF Power Output Check
Suppose you wish to read the transmitter output power while the HHT is connected. The
following steps will accomplish this.
1. Connect the transceiver to a dummy load.
2. Type
KEY
+
ENTER
, to key the transmitter.
3. Type
FPWR
+
ENTER
, to display the forward power output level.
4. As a further performance check, the DC voltage supplied to the transmitter can be
read by typing
SV
+
ENTER
.
5. Unkey the transmitter by typing
DKEY
+
ENTER
.
Received Signal Strength Indication (RSSI) Check
To invoke the RSSI function, simply type
RSSI
+
ENTER
on the HHT. The display indicates
the signal level at the
ANTENNA
connector in dBm. The display is updated once every second.
This check can be especially useful when aiming the antenna at the remote site for maximum
signal level. By using the RSSI command and the continuously updated display, an installer
can aim the antenna in the direction of maximum field strength.
Table 3-1. Diagnostic and Control Capabilities
LEVEL MODE DESCRIPTION
Loopback 1 A radio set to Mode 1 diagnostics will respond to a poll containing a four-digit
number string called the “Loopback Code.” When the remote radio decodes
its loopback code transmitted by an MDS master station, it responds by
keying its transmitter for several seconds with a continuous modulating tone.
The radio’s signal strength and deviation can then be measured by the
Master Station.
Advanced 2 With a radio set to Mode 2, critical diagnostic information available through a
local HHT or personal computer is available over the RF channel to the
Master Station. This includes: transmitter RF power output, the primary
power supply voltage, the in8 Vdc regulated voltage level, the
synthesizer’s lock voltage and the radio’s internal temperature. In addition,
the diagnostic analysis of the remote unit’s signal, as received by the Master
Station receiver will be displayed on a personal computer connected to the
master station. These values include received signal level, carrier frequency
offset (error) and modulation level/deviation.
Remote
Maintenance 3 This is the highest level of diagnostics and control capability available for the
MDS 4310 transceiver. With Remote Maintenance enabled, all of the above
diagnostic capabilities are available and, in addition, many of the radio’s
parameters can be adjusted either locally with an HHT or over the RF
channel with a personal computer running MDS 2000 Diagnostic and Control
System software. Since it provides the greatest level of diagnostics and
control, many users prefer to keep the transceiver set to Mode 3 diagnostics.