Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
5. Switch off the squelch and make sure that you now hear a 1600 Hz tone.
6. To control the limiting amplifier connect the oscilloscope to the output of the operational amplifier
U02/1, pin 1. Control the measured signal to be squarewave with a frequency of 1600 Hz and an
amplitude of about 13Vpp.
7. To control the frequency to voltage converter, connect the voltmeter to the output of the operational
amplifier U02/4, pin 14 and control the DC voltage to be about 7V.
8. Increase the generator frequency with 1 kHz and control the DC voltage at U02/4, pin 14, to
increase to about 11V. Decrease the generator frequency with 2 kHz (f
G
= 1990.6 kHz) and control
the DC voltage to decrease to about 4V.
9. To control the voltage change detector, connect the oscilloscope to the output of the operational
amplifier U01/4, pin 14. Select DC trig mode and positive slope trig.
10. Change the generator frequency with +/-1 kHz relative to the frequency specified in point 15 and
control in each case the voltage change detector to generate an impulse with a magnitude of about
13V and a duration of about 350 msecs.
11. To control the Hold Circuit, choose the generator frequency specified in point 15, and switch on the
squelch.
12. Connect the voltmeter to the output of the operational amplifier U01/1, pin 1.
13. Decrease the generator frequency with 1 kHz and control the DC voltage at U01/1, pin 1 to be about
13V. You will now hear a 600 Hz tone in your handset or loudspeaker.
14. Control the DC voltage at U01/1, pin 1 to fall to 0V after a time period of about 10 secs and control
that the audio frequency output is muted.
15.
3.6.2 MODULE PERFORMANCE CHECK OF FRONT END UNIT
This chapter contains the following sections:
3.6.2.1. Check of Sensitivity (RE2100)
3.6.2.2. Check of Front End Gain
3.6.2.3. Check of Mute and RX/TX Switch
3.6.2.4. Check of Selection Circuit for Pre-Filters
3.6.2.5. Check of LO1 Signal and Buffer
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