Installation Manual

Table Of Contents
Related Links
Tuning the Modulation Limit (with no Tx Data and no PL) on page
75
Verifying the Modulation Limit (with no Tx Data and no PL) on page 76
8.7.1
Tuning 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 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.
4 Launch the Tuner application.
5 To read the softpot values, click Read.
6 In the tree view, select TX, then select Modulation Limit.
7 Enter the tuning frequency into the Communication Analyzer (the value displayed on the Tuner
application).
8 To key up the repeater, click PTT Toggle.
9 Adjust the softpot value until the maximum deviation is 92% of the rated system deviation
(RSD).
This adjustment is tested in a 12.5 kHz channel spacing, so 92% of 2.5 kHz is 2.3 kHz.
10 Set the modulation limit to 92% so that any additional deviation incurred by the transmitter VCOs
over temperature is compensated for.
Channel Spacing
(kHz)
RSD (kHz) 92% of RSD (kHz) Tolerance (Hz)
12.5 2.5 2.3 +0/ -50
11 To de-key the repeater, click PTT Toggle.
12 To save the new tuned softpot value into the repeater codeplug, click Write.
Return to Process
Modulation Limit Alignment on page 74
MN003557A01-AF
Chapter 8: SLR 1000 Programming and Tuning
75