4-22 FIELD TESTS & ADJUSTMENTS MDS 05-2415A01, Rev. A
13. Enter the received signal strength command, RSSI, from the HHT. Type RSSI +
ENTER . The display shows the current received signal level in dBm. Check the
calibration with the communications service monitor set between –60 dBm (225 µV)
and –120 dBm (.225 µV).
14. This completes the calibration procedure. Disconnect the HHT and communications
service monitor.
Testing The Remote Transceiver With The Master Station—Optional Checkout
This section provides abbreviated instructions for testing Remote Maintenance with a
properly equipped Master station on a service bench. This test simulates over-the-air Remote
Maintenance using a PC and MDS 2000 Diagnostics and Control System software. Complete
instructions for using the software are contained in the MDS 2000 Diagnostics and Control
System software User’s Guide (P/N 05-1919A01).
1. Connect the transceiver to the Master Station using coaxial cable through at least
100 dB of attenuation. The attenuators at each end of the connection should be rated
to continuously withstand at least 5 watts of RF power.
2. Attach the PC through one of its serial ports to the
DIAGNOSTIC connector on the rear
of the MDS 2100 Master Station.
3. Set the Master Station’s rear-panel DTE/DCE switch to DCE if you’re using a
straight-through serial cable, or DTE if you’re using a null-modem cable.
4. Load the MDS 2000 Diagnostics and Control System software on the PC and open
the Diagnostics Channel to the Master Station.
5. Using the software’s Equipment List Editor, select the Remote transceiver to be
tested and set the radio’s diagnostic level to Remote Maintenance.
6. Return to the polling screen and verify that you can perform a diagnostic poll on the
remote radio.
7. Press
F4 to invoke Remote Maintenance. The Remote Maintenance screen for that
transceiver appears. (See Figure 4-8.)
8. The software displays the Remote radio’s transmit frequency error compared to the
master station’s receive frequency. The offset (or difference) should be within 0.3
kHz; If not, adjust the MDS 4310 transmit frequency as described in the Field
Alignment instructions in this chapter.
9. Verify that the DTMF deviation display indicates approximately 2.5 kHz. If no
modem is installed in the transceiver, skip ahead to Step 11. Otherwise, proceed with
Step 10.
10. Press F3 to toggle the deviation display from DTMF to DATA. If the data deviation
is 2.7 kHz ±0.2 kHz, proceed to the next step. If not, adjust the MDS 4310 deviation
as described in the Field Alignment instructions in this chapter.
11. If the power output is not set to the desired output level (usually 5 watts), use the
← → arrow keys to select the POWER bar and the ↑ ↓ arrow keys to increase or
decrease the output level as desired. The POWER bar also shows the reflected power
level and includes a VSWR summary—OK, CHECK SYS, or BAD.
12. Press F4 to store the changes within the Remote Maintenance Module.
13. Press
Esc to close Remote Maintenance of that Remote unit and return to the
previous screen.
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