Sailor RE2100, Техническое руководство

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3 SERVICE RE2100
3.7.3 ADJUSTMENT PROCEDURE FOR EXCITER UNIT
This chapter contains the following sections:
3.7.3.1. Adjustment of Compressor and AF Limiter
3.7.3.2. Adjustment of Carrier Limit Amplifier
3.7.3.3. Adjustment of Modulator
3.7.3.4. Adjustment of RF Limiter
3.7.3.5. Adjustment of Carrier Insertion
3.7.3.6. Adjustment of Step Attenuator
3.7.3.7. Adjustment of 70 MHz IF
For best stability, all coils and transformers are adjusted with the cores in the lower resonant position.
For each circuit to be adjusted, it is a condition that all the previous circuits are adjusted to obtain the best
possible adjustment.
In the adjustment procedure for the Exciter Unit, four service programmes are used, SP-05-0, 1, 2, and
3. How to select the service programmes is described in section 3.10.1.
3.7.3.1 ADJUSTMENT OF COMPRESSOR AND AF LIMITER
The compression level is adjusted by R35-4 and the cutting symmetry is determined by R57-4.
1. Connect the scope probe to the emitter of Q04-4 (TP1-4).
2. Select service programme SP-05-0.
3. A combined square wave signal (tune tones) is seen on the scope.
4. Turn R35-4 clockwise until the signal reaches a limiting level.
5. Adjust R57-4 to obtain a symmetrical cutting of the signal. That is, when both top and bottom of the
signal reach the limiting level simultaneously when the signal is increased by means of R35-4.
6. Turn R35-4 fully clockwise.
7. Adjust the scope until there is full deflection (8 div.) on the scope.
8. Adjust R35-4 until the deflection seen on the scope is 7 div. peak-peak. The signal is now under
the limiting level.
9. If this adjustment is the only one executed after repair, please execute 3.7.3.4. Adjustment of RF
Limiter.
3.7.3.2 ADJUSTMENT OF CARRIER LIMIT AMPLIFIER
1. Connect scope probe to the connection between R93-4 and C75-4 (TP2-4).
2. Select service programme SP-05-0.
3. Press handset key.
4. Adjust L05-4 to maximum signal.
5. Release handset key.
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