Codan 2110 series, Repair Manual

Page: 105 / 164

Repair procedures, tests, and adjustments
Manpack Transceiver 2110 series Repair Guide 73
Performing the Distortion test using an oscilloscope
To test distortion and spurious signals using an oscilloscope:
1
Set up the equipment (see page 56, Setting up the test equipment ).
1
Select a channel to test.
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 RF envelope using Figure 20 , Figure 21 , Figure 22 , and Figure 23 .
Figure 20: Acceptable two-tone RF envelope
Figure 21: Defective two-tone RF envelope (typical overbias of PA)
Pass The RF waveform envelope is acceptable.
NOTE
If the waveform is acceptable, there is no need to perform the
Intermodulation test.