User's Manual

Figure 37: Test Equipment Setup for Verifying Transmitter Circuitry
HELP
TAB
1
SELECT
CANCEL
IFR390I Digital Radio Test Set
TEST
HOLD
CONFIG
UTILS
ENTER
MIC/ ACC GEN T/R ANT
RETURN
TESTPORT CH1 SCOPE CH2 1 2AUDIOINFCTNGEN/DEMOD OUT
0
.
#
ASSIGN
–
*
2
4 5 6
7
HELP
8 9
3
T/R
Power Meter
Dummy Load
Tx
(Step 5)
Microphone
(GMMN4063_)
9.3
Receiver Testing
CAUTION:
Performing this procedure requires that the repeater be taken out of service. It is recommended
that, unless the SLR 5000 Series Repeater is already out of service, this procedure be
performed during
off-peak hours so as to minimize the disruption of service to the system subscribers.
If the repeater operates as a repeater, the transmit output from the repeater must be connected
to a dummy load to prevent over-the-air broadcast during Receiver testing.
9.3.1
Introduction
While most module faults can be detected by running the SLR 5000 Series Repeater diagnostics, the
following procedure provides a more traditional method of troubleshooting the Receiver circuitry.
This procedure allows the service technician to make minor adjustments and verify proper operation of
the receiver circuitry on the Modem Module.
In general, the Receiver circuitry is exercised by injecting and measuring signals using a Service
Monitor (or equivalent). Incorrect measurement values indicate a faulty module(s); measurement
values within the acceptable range verify proper operation of the receiver circuitry on the Modem
Module.
9.3.2
Required Test Equipment
The following test equipment are required to perform the procedure:
• Aeroflex 3920 Digital Radio Test Set (or equivalent)
• Service Speaker (part no. HSN1006_)
• Station Rear Accessory Test Cable
• Dummy Load (50 Ω, repeater wattage or higher) required for repeaters only
MN001436A01-AD
Chapter 9: SLR 5000 Series Performance Check or Testing
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