Sailor RE2100, Technical Manual

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3 SERVICE RE2100
9. Adjust R92-4 until the deflection on the screen of the carrier signal is 4.4 div.
10. Release handset key.
3.7.3.6 ADJUSTMENT OF STEP ATTENUATOR
1. Connect scope probe to emitter of Q18-4 (TP5-4).
2. Select service programme SP-05-0.
3. Press handset key.
4. Adjust L09-4 to maximum signal.
5. Release handset key and press <ENT> on the keyboard.
6. Select service programme SP-05-2.
7. Connect another scope probe to R143-4 (TP6-4). This signal is used to trig the scope. The scope
must be trigged by the negative transition.
8. On the scope is now seen a staircase waveform. When adjusting R159-4 it can be seen that one
of the steps changes amplitude.
9. Adjust R159-4 until the step, which changes amplitude, is approximately equal to the neighbour
steps.
10. Press <ENT> on the keyboard.
11. To adjust the RF output power level from the Exciter Unit to the Power Unit (8), it is a condition that
both the 70 MHz IF filter and the Power Unit are correctly adjusted. If not, perform section 3.7.3.7.
and 3.7.4.2.
12. Connect a 50 ohm resistor to the aerial socket. Two 100 ohm resistors in parallel soldered on a coax
cable connected to the aerial socket are sufficient.
13. Connect an oscilloscope through a 10:1 probe to the 50 ohm resistor.
14. Select service programme SP-05-0.
15. Press handset key.
16. Adjust R120-4 until the signal on the scope is 3.5 Vpp. If a milliwattmeter is connected to the aerial
socket J01-2 it should read 12 dBm in 50 ohm.
17. Release handset key.
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