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

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MDS 05-2415A01, Rev. A TROUBLESHOOTING 6-3
3. Antenna System Evaluation
a. Inspect antenna for damage; the feedline for loose, shorted or waterlogged
connections.
b. Check forward and reflected power at
ANTENNA
connector of transceiver using
in-line wattmeter (VSWR should be less than 1.5:1).
4. Interface Functions Evaluation
a. Check for secure interface connections at the RTU and at the transceiver.
b. Check the RTS/CTS delay setting—it should be normally be set to a minimum
of 10 ms.
c. Check to see if data is lost at beginning or end of transmission. If lost at
beginning, suspect problem with RTU keyline interface; if at end, squelch tail or
soft carrier dekey timing problems.
d. If soft carrier dekey is needed, check for proper programming of delay with
HHT or PC terminal.
e. If noise from the squelch tail (closing) is interfering with the data flow, then
enable the Squelch Tail Eliminator function in the MDS 4310 using the
ESTE
command with the HHT. (Applies to analog systems only.)
f. Check for excessive length of the interface cable. This cable should be only as
long as necessary to reach the radio. If the length exceeds 50 feet, then an
RS-232 to RS-422 Converter Assembly may be required. (MDS P/N 01-
2358A01.)