Codan 2110 series, Руководство по ремонту

Страница: 96 / 164

Repair procedures, tests, and adjustments
64 Manpack Transceiver 2110 series Repair Guide
1
Switch the 0208 speaker to
Speaker
.
1
Return the antenna to the 50

connector ( ).
1
Return the Cfg Auto Tune Mode to
ATU/50 Ohm/Codan
.
1
Return to the Repair flowchart (see Figure 29 on page 95 ).
Performing the Sensitivity test
To test the sensitivity of the transceiver to received signals:
1
Set up the equipment (see page 56, Setting up the test equipment ).
1
Select a channel to test, preferably near the centre of one of the designated bands
(see
page 60, Examining the profile in the transceiver ).
1
Adjust the volume via the front panel to full volume.
1
Set the RF signal generator to 1.0 kHz above the SCF of the selected USB channel
or 1.0 kHz below the SCF of the selected LSB channel.
1
Switch off the RF output from the RF signal generator.
1
Set the 0 dB reference on the AC voltmeter to the level of the background noise
(approximately –28 dBm).
1
Set the RF output level of the RF signal generator to –120 dBm.
1
Switch on the RF output from the RF signal generator.
1
Record your results and actions (see page 109, Test sheet for the 2110 series
Manpack Transceiver ).
1
Switch off the RF pre-amp in the transceiver.
1
Repeat the test, this time setting the 0 dB reference on the AC voltmeter to the level
of the background noise (approximately –31 dBm).
1
Set the RF output level of the RF signal generator to –114 dBm.
1
Switch on the RF output from the RF signal generator.
1
Record your results and actions (see page 109, Test sheet for the 2110 series
Manpack Transceiver ).
1
Switch off the RF output from the RF signal generator.
1
Switch on the RF pre-amp in the transceiver.
1
Return to the Repair flowchart (see Figure 29 on page 95 ).
NOTE
Meter damping may be required in noisy environments.
Pass A reading on the AC voltmeter that is an increase of > 10 dB from
the 0 dBm reference point.
Pass A reading on the AC voltmeter that is an increase of > 10 dB from
the 0 dBm reference point.