Codan MT-4E, Руководство по обслуживанию

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MT-4E ANALOG & P25 DIGITAL RADIO SYSTEMS | MAINTENANCE GUIDE
Chapter 5: Codan Radio System Testing Page 53
Deviation Level:
Check the deviation level. Ideally the deviation level out of the transmitter should match the input to the
receiver. The repeater deviation level matching is adjusted by the analog LVDS level adjustment that
is available in both the receiver and transmitter (only one needs to be adjusted).
In the receiver or transmitter RSS, enter the Service section and click on “LVDS Level”. A default
value of 100 on the softpot slider should be close to matching receiver and transmitter deviation levels,
however minor adjustments can be made. Adjust the softpot slider in the RSS as shown in Figure 5-41
until a deviation of +/- 1.5 KHz (narrowband) or +/- 3.0 KHz (wideband) is measured on the IFR 2975.
The low and high alarms are set for 1.40 KHz and 1.60 KHz.
Figure 5-41: RSS Receiver or Transmitter Analog LVDS Level Adjustment
Enter the Repeat Deviation Level reading on the MT-4E Test Sheet.