Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
AM MODE
21. Repeat points 1, 2 and 4-6.
22. Make sure that H3E mode (AM) is selected.
23. Repeat point 8-11.
24. Increase generator output level V
G
by 6 dB.
25. To check the 6 dB bandwidth, key-in the frequencies 986,7 kHz and 993.3 kHz, and control in each
case the voltage at testpoint TP1-1 to be above 5 volt. Remember in each case to turn off the AGC.
26. Increase generator output level V
G
by 36 dB relative to V
G
in point 20.
25. To check the stopband attenuation, key-in the frequencies 982,9 kHz and 997,1 kHz, and control
in each case the voltage at testpoint TP1-1 to be below 5 volt. Remember in each case to turn off
the AGC.
3.6.1.4 CHECK OF 2nd IF AMPLIFIER
In this test the gain of the 2nd IF amplifier is controlled by checking the threshold level of the Automatic
Gain Control.
This threshold level is defined in the figure below, where the AGC-characteristic is sketched.
4-0-26210
AGC-characteristic used to define the sensitivity or threshold level of the AGC.
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