Motorola R-2001A Service Manual page 74

5. AHernatety ad/usl She Iwo SWAD Noich polenf/ome'ters on 8ie Scope/DVW Coniro) Board iF/gare
5-20) for a maximum SINAD reading on the CRT display. A reading greater than 30 dB should be
obtained.
6: Turn the system power off and reinstall the Scope/DVM Control Board into the R2001A.
5-122. Receiver
5-123. AM Detector
1. Perform the basic alignment procedure of para 5-105.
2. Turn the R2001 A off and remove the Receiver Module. Remove the Receiver Module cover and install
the Receiver Test Cover on the module housing. Extend the Receiver module on the Receiver Extender
Card.
3. Turn the R2001 A on and select the Monitor AM Function and the Gen/Mon Mtr Display. Set the monitor
frequency to 250 MHz, the RF Step Attenuator to the 0 dB position, and the BW Switch to the Narrow
position.
4. Connect the external signal generator to the RF In/Out Jack on the front panel. Adjust the external
generator for an output level of approximately -60 dBm and a calibrated 30% AM.
5. Adjust R60 (Marked on the Receiver Test Cover) for a reading of 30% ±5% on the CRT AM display.
5-124. FM Detector
1. Select the Monitor FM Function and the Gen/Mon Mtr Display. Set the monitor frequency to 250 MHz,
the RF Step Attenuator to the 0 dB position, and the BW Switch to the Wide position.
2. Connect the external signal generator to the RF In/Out Jack on the front panel. Adjust the external
generator for a center frequency of 250 MHz at an output level of approximately -30 dBm and a
calibrated 20 kHz FM.
3. Adjust R70 (Marked on the Receiver Test Cover) for a reading of 20 kHz ± 1 kHz on the CRT FM display.
4. Set the BW switch to the Narrow position and reset the FM on the external generator to 3 kHz deviation.
5. Adjust R125 (Marked on the Receiver Test Cover) for a reading of 3 kHz ± 150 Hz on the CRT FM
display.
6. Turn off the FM on the external generator so that a CW signal of a level of approximately -30 dBm is
applied to the R2001A.
7. Connect the Demod Out Jack to the Vert/Sinad/DVM/Counter I nputdaek on the front panel. Select the
DVM Display and the DC DVM Mode on the R2001A.
8. Adjust R68 (Marked on the Receiver Test Qover) for a 0.0 VDC ±100 mVDC reading on the DVM
Display. I
5-31
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