Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
3. Adjust the manual RF-gain until the DC-output voltage from the AGC level detector is about 5V.
4. Tune the trimming capacitor C18-1 to maximum meter deflection.
5. Press <TUNE> to leave the service programme mode.
3.7.1.4 ADJUSTMENT OF 2nd IF-GAIN (Receiver)
To meet the gain variations from one transistor to another, the 2nd IF-amplifier has been constructed with
a reserve of power gain. This implies that the 2nd IF-gain may be very large, which may cause unstable
conditions because of unwanted feedback.
It is therefore necessary to adjust the unregulated gain of the 2nd IF-amplifier, which must be done in
accordance with the procedure given below.
The 2nd IF-gain is adjusted by trimming the resistor R203-1, which is located at the receiver unit (module 1).
The adjustment is performed by using a signal generator and an AC voltmeter.
1. Connect the signal generator to the aerial socket at the front end unit.
2. Connect the AC voltmeter to earpiece output at testpoint TP2-1.
3. Turn the RE2100 on.
NOTE! The RE2100 must be on for at least five minutes before proceding.
4. Select the setting of the signal generator and the RE2100 according to point 5.
5.
6. Measure the AC voltage at the earpiece output.
7. Change the generator output level to 0dB/uV.
8. Adjust the resistor R203-1 until the AC voltage at earpiece output is decreased by 4 dB relative to
the level measured in point 6.
3.7.1.5 ADJUSTMENT OF SIGNAL METER (Receiver)
The signal meter is adjusted by trimming the resistor R76-1, which is located at the receiver unit (module1).
1. Disconnect any input to the aerial socket.
2. Turn the RE2100 on and make sure that J3E-mode (SSB) is selected and that the AGC is operative.
3. Adjust R76-1 until the first LED-bar in the display is just about to light.
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