Transmitter Compressor Measurement; Audio/Data Level Adjustments; S100 Setting - Viking 242-2009-632 Service Manual

900 mhz ltr-net 75w-160w repeater
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ALIGNMENT AND TEST PROCEDURES
7.6.7 TRANSMITTER COMPRESSOR MEA-
SUREMENT
NOTE: This test is valid only with compandor option
installed.
1. Set the modulation analyzer LPF to 3 kHz.
2. Apply +7 dBm (1.73V RMS) at 1 kHz to P100, pin
32 on the MAC.
3. Use the "Turn on carrier" button to key the transmit-
ter.
4. Deviation shall be between 1.35 and 1.5 kHz.
5. Adjust 1 kHz signal to -8.2 dBm (300 mV RMS).
Deviation shall be between 750 and
850 kHz.
6. Adjust 1 kHz signal to -17.8 dBm (100 mV RMS).
Deviation shall be between 450 and
500 kHz.
7. Use the "Turn on carrier" button to unkey the trans-
mitter.

7.6.8 AUDIO/DATA LEVEL ADJUSTMENTS

NOTE: Section 7.6.6 must be completed before any of
the following adjustments can be made.
NOTE: All audio generators and audio voltmeters are
unbalanced unless specifically stated otherwise.
Voice Audio From Repeater
1. Set MAC S100 and S101, all Sections OFF.
2. Adjust the RF generator for 100 V modulated with
a 1 kHz tone at 1.5 kHz deviation.
3. Connect a balanced AC voltmeter with a 600 ohm
input impedance between balanced lines RXA+ and
RXA- on J2, located on the back of the Repeater.
March 1999
Part No. 001-2009-600
4. Adjust R239 on the MAC for the type of line.
Leased Line/Direct Connect (default)
-12 dBm (194 mV RMS)
Microwave/T1 (optional)
-28 dBm (31 mV RMS)
Voice Audio To Repeater
1. Set MAC S100 and S101, all Sections OFF (see
Figure 7-12).
2. Inject a 1 kHz tone from a balanced 600 ohm
source, at the level determined by the type of line
used, into TXA+ and TXA- of J2 located on the
back of the Repeater (see Figure 7-12).
Leased Line/Direct Connect (default)
-12 dBm (194 mV RMS)
Microwave/T1 (optional)
-28 dBm (31 mV RMS)
3. Adjust R243 on the MAC to obtain -6 dBm (387
mV RMS) measured at J100/J103.
Figure 7-12 S100 SETTING
FSK Data Level Adjustment To Repeater
Separate Data Path (4-Wire) Optional Setting.
1. Set MAC S100 Sections 1, 4, 5, 8 OFF; 2, 3, 6, 7
ON; S101 Sections 2, 3, 4 OFF; 1 ON (see Figure
7-13).
7-18

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