Microwave Data Systems MDS 4310, Установка, эксплуатация и техническое обслуживание на месте

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MDS 05-2415A01, Rev. A FIELD TESTS & ADJUSTMENTS 4-7
NOTE
The transmitter will be turned off by the time-out timer if the
transmit period exceeds the programmed time out value. To
continue
testing, simply unkey and key the transmitter to reset
the timer. The factory default value for the time-out timer is
180 seconds.
If desired, the time-out timer may be disabled during these
tests, by sending the
DTOT
command from the HHT keypad. Be
sure to restore the timer to its original setting when testing is
complete.
NOTE
The Diagnostics Channel (the link between the HHT and the
radio) “times out” after 15 minutes of no HHT keypad activity.
If this happens, you will need to re-open the Diagnostics
Channel to resume transceiver testing.
TEST PROCEDURE
➊
:
BASIC TRANSCEIVER CHECKS—Applicable to all hardware configurations
Introduction
This section describes basic checks that apply to all common configurations of the MDS
4310 transceiver. The checks covered are:
• Power supply
• Transmitter power output
• Antenna VSWR
These checks should be made before starting any detailed troubleshooting or alignment of the
transceiver. See Figure 4-9 for the locations of adjustable controls on the transceiver
motherboard.
Power Supply Check
1. Connect the power supply to the transceiver.
2. Remove the transceiver’s cover by loosening the four captive screws along the
perimeter of the case.
3. Measure the power supply voltage at the transceiver power connector.
R
M
With Remote Maintenance installed, the supply voltage can be checked by
entering the
SV
command on the Hand-Held Terminal.
If necessary, adjust the power supply voltage to 13.8 Vdc. If the voltage is not
adjustable, make sure the nominal value is between 12 and 15 volts.
4. Momentarily key the transmitter by the
KEY
and
DEKEY
commands.
5. The voltage should drop no more than 0.4 Vdc while the transceiver is keyed.