Codan 2110 series, Руководство по ремонту

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Repair procedures, tests, and adjustments
Manpack Transceiver 2110 series Repair Guide 65
Performing the AGC test
To test the AGC of the transceiver:
1
Set up the equipment (see page 56, Setting up the test equipment ).
1
Select a channel to test.
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
Set the RF output level of the RF signal generator to –13 dBm.
1
Adjust the volume via the front panel so the tone is clearly audible.
1
Set the 0 dB reference on the AC voltmeter to the level of the tone (approximately
–5 dBm at full volume).
1
Reduce the RF output level of the RF signal generator until the reading on the AC
voltmeter reduces by 6 dB.
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
Return to the Repair flowchart (see Figure 29 on page 95 ).
Performing the Audio Output test
To test the audio output from the transceiver:
1
Set up the equipment (see page 56, Setting up the test equipment ).
1
Replace the AC voltmeter with an oscilloscope.
1
Adjust the oscilloscope to view a 1 kHz tone at 1 V p–p.
1
Select a channel to test.
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
Set the RF output level of the RF signal generator to –60 dBm.
1
Switch on the RF output from the RF signal generator.
1
Switch the 0208 speaker to
Load
.
Pass An RF output level from the RF signal generator that is < –106 dBm
(RF pre-amp on).
NOTE
This is typically 0.2 V/div, sweep 0.5

s/div.