Sailor RE2100, Technical Manual

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3 SERVICE RE2100
3.6.4.3 CHECK OF MODULATOR
1. Select service programme SP-05-0 and press handset key.
2. Connect a scope probe to U06-4, pin 10 and read approx. 0.17Vpp.
3. Connect scope probe to U06-4, pin 1 and read approx. 0.75 Vpp.
4. Connect scope probe to the connection between C66-4 and C67-4 (TP3-4) and read the voltage
to 6.6 Vpp +/-0.3V.
3.6.4.4 CHECK OF SSB FILTER
1. Connect a tone generator to the testbox at the BNC-socket “AF to TX”. If a testbox is not available,
connect the tone generator directly to the handset plug on the RE2100 (to J03-2, pin 4). Connect
it with a capacitor 22 uF/25V because of the DC voltage on the microphone terminal. Set the tone
generator output level to 0.3 Vpp.
2. Select service programme SP-05-1 and select J3E mode on the keyboard.
3. Press handset key.
4. Connect a scope probe to Q19-4 emitter (TP4-4).
5. Control of SSB filter response is carried out by changing the frequency of the tone generator and
controlling the reading on the scope. Max. permissible ripple is 2 dB in the frequency range 500
Hz to 2500 Hz and the -6 dB frequency is approx. 350 Hz and 2700 Hz.
3.6.4.5 CHECK OF RF LIMITER AND CARRIER INSERTION
1. Select service programme SP-05-0 and press handset key.
2. Connect the scope probe to Q19-4 emitter (TR4-4) and read the voltage to approx. 1.5Vpp.
3. Short-circuit R34-4 (TP7-4) to ground, and the signal seen on the scope is now cut.
4. Adjust the scope until full deflection (8 div) of the cut signal is seen on the scope screen.
5. Disconnect the grounding of R34-4 and read on the scope the peak-peak voltage to be
7.2 div. +/-0.2 div.
6. Adjust the scope until full deflection of the signal is seen on the scope screen.
7. Select service programme SP-05-1 and press handset key.
8. Select H3E mode on the keyboard.
9. Check on the scope that the signal is 4.4 div. +/-0.3 div.
10. Select R3E mode on the keyboard.
11. Check on the scope that the signal is 1.2 div. +/-0.2 div.
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