Installation Manual

8.7.2
Verifying the Modulation Limit (with no Tx Data and no PL)
Prerequisites: Obtain the following:
•
Wattmeter (Communication Analyzer)
• Service monitor or counter
• 20 dB pad
• Standard Type A to Type B USB cable
• Personal computer
Procedure:
1 Connect the repeater antenna port to the attenuation pad, if necessary, before connecting to the
Communication Analyzer.
2 Power the repeater from a DC source.
3 In Radio Management (RM), program the repeater with any frequency within the specified range
of the repeater under test, and set the repeater for low power and disable the repeat path.
4 Apply a 1 kHz signal at 1.2 Vrms to Pin 1 of the Aux connector.
Signal ground is Pin 4 of the Aux connector.
5 Key up the repeater by grounding Pin 2 of the Aux connector and measuring the deviation
NOTICE: Radio Management
must have Pin 2 configured as an active low with the PTT
function.
6 De-key the repeater.
The deviation should meet the limits shown in the following table.
Channel Spacing
(kHz)
Relative Standard Deviation (RSD)
(kHz)
92% of RS
(kHz)
Tolerance
(Hz)
12.5 2.5 2.3 +0/-50
20.0 4.0 3.68 +0/-80
25.0 5.0 4.6 +0/-100
NOTICE:
•
The repeater is factory-tuned in accordance to this procedure and specification.
• Verification is performed outside of the Tuner application, such as in normal mode.
Return to Process
Modulation Limit Alignment on page 74
8.8
Tuning a Duplexer Module
The duplexer module is shipped untuned. Before installing the duplexer into the repeater, it must be
tuned specifically to the transmit and receive frequency pairs of the repeater.
The duplexer module is composed of three low-pass/high-notch cavities and three high-pass/low-notch
cavities. Each set of three cavities provides bandpass filtering for either the transmit RF signal or the
receive RF signal. In general, the duplexer must be tuned so that the transmit cavity set passes the
MN003557A01-AF
Chapter
8: SLR 1000 Programming and Tuning
76