Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
8. Control with the counter the output frequency to be 930 Hz +/-10 Hz.
NOTE!
The frequency tolerance of the signal generator shall be better than +/-2.5 Hz 0.1 ppm. If not and
if the counter has a frequency tolerance of 0.1 ppm, carry out the measurement in section 3.5.3.2.
Performance Check of Exciter Frequency.
3.5.2.5 PERFORMANCE CHECK OF RECEIVER AGC
1. Connect the signal generator to the aerial socket through a 50 ohm dummy load.
2. Connect a voltmeter to the 0 dBm output on the testbox.
3. Choose receiver frequency f
RX
, generator frequency f
G
, and generator output level V
G
according to
the table in point 4.
4.
5. Turn the RF-GAIN control fully clockwise, and make sure that the AGC is operative.
6. Notice the AF output level by means of the voltmeter at the 0 dBm output.
7. Increase the output level of the signal generator to 28 dB/uV.
8. The increase in AF output level measured with the voltmeter shall be less than 3 dB.
9. Notice the AF output level by means of the voltmeter at the 0 dBm output.
10. Turn the AGC OFF and adjust the RF-GAIN control to achieve the output level found in point 9.
11. Disconnect the signal generator from the aerial socket and notice the reduction of the AF output
level, which shall be at least 35 dB.
12. Reconnect the signal generator to the aerial socket.
13. Turn the RF-GAIN control fully clockwise and make sure that the AGC is operative.
14. Notice the AF output level by means of the voltmeter at the 0 dBm output.
15. Increase the output level of the signal generator to 78 dB/uV.
16. The increase in AF output level measured with the voltmeter shall be less than 2 dB.
17. Connect 0 dBm output from the testbox to channel A on the oscilloscope.
18. Connect the SP-BUS output socket on RE2100 to channel B on the oscilloscope.
19. Select test programme SP-04-6.
20. Set the timebase on the oscilloscope to 20 msecs/div.
21. Set the oscilloscope to trig on channel B.
22. Control that the oscilloscope displays the response shown in figure SSB attack.
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