Codan 2110 series, Repair Manual

Page: 107 / 164

Repair procedures, tests, and adjustments
Manpack Transceiver 2110 series Repair Guide 75
Performing the Intermodulation test using a spectrum analyser (optional)
To test the intermodulation products using a spectrum analyser:
1
Set up the equipment (see page 56, Setting up the test equipment ).
1
Connect the spectrum analyser via a high input impedance probe to the 50

connector ( ) with the dummy load still connected.
1
Select any channel in Band 1.
1
Set up the spectrum analyser as follows:
1
Switch on PTT on the 0208.
1
Adjust the output level of the 0208 until the RF output power of the transceiver stops
increasing, then increase the output level of the 0208 by 10 dB.
1
Analyse the display on the spectrum analyser using Figure 24 .
Figure 24: Intermodulation measurements using a spectrum analyser
1
Record your results and actions (see page 109, Test sheet for the 2110 series
Manpack Transceiver ).
Centre frequency Carrier frequency
Frequency span 20 kHz
Video bandwidth 300 Hz
Trigger Continuous sweep
Vertical scale 10 dB per division
Reference level Adjust once the transceiver is transmitting at full power
Pass Intermodulation products are 26 dB down.
IMD measurement
(below each tone)