Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
12. Connect a frequency counter through a 10:1 probe to the 50 ohm resistor at the HF output socket.
13. Control that the frequency is 28,000,000 +/-10 Hz.
NOTE! The frequency tolerance of the counter shall be better than 0.1 ppm.
14. Set the testbox switch RF 50% DUTY CYCLE on.
15. Connect the oscilloscope through a 10:1 probe to the 50 ohm resistor at the HF output socket, and
disconnect the frequency counter.
16. The HF signal seen on the oscilloscope screen is switched on for 250 msecs and then off for 250
msecs.
17. Control that the attack time of the HF signal is not more than 2 msecs, and that the decay time is
not more than 3 msecs.
18. Set the testbox switch RF 50% DUTY CYCLE off and the testbox switch RF ON/OFF off.
If TELEX MODE is possible carry out the following points, if not go to the next section 3.5.3.3.
19. Connect the LF signal generator to the AF TO TX input on the testbox.
20. Adjust the LF signal generator output to 3Vpp/1600 Hz.
21. Select the emission mode TELEX on RE2100.
22. Set the testbox switch MIC.KEY on.
23. Control that the HF output shown on the oscilloscope is 4.0 +/-0.5Vpp.
3.5.3.3 PERFORMANCE CHECK OF EXCITER MICROPHONE AMPLIFIER AND
LF RESPONSE
1. If only this chapter is performed, please start by carrying out the section 3.5.3.1. point 1, 2, and 3.
2. Select test programme SP-05-6 (f
TX
= 1.600 kHz).
3. Set the testbox MIC-KEY on.
4. Set the LF signal generator frequency to 1Vpp/1600 Hz.
5. Adjust the LF signal generator frequency until the deflection seen on the oscilloscope is max.
approx. 1600 Hz.
6. Adjust the oscilloscope gain until full deflection (8 div.) is seen on the screen.
7. Adjust the LF signal generator frequency to 350 Hz and to 2700 Hz and control that the deflection
seen on the oscilloscope screen is above 4.0 div.
8. Set the LF signal generator frequency to 1.0Vpp/1000 Hz.
9. Adjust the oscilloscope gain until full deflection (8 div.) is seen on the screen.
10. Adjust the LF signal generator output level until the HF output level seen on the osilloscope is
approx. 7.5 div.
11. Control that the LF signal generator level at the input of the testbox is now 100 +/-50 mVpp.
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