Motorola PDR 3500, Базовое руководство по обслуживанию

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68P81093C75-O September 27, 2000 9-41
Step 2. Remove the chassis from its case by removing the
eight Phillips screws from the edges of the station’s
top panel.
Step 3. Remove the two Torx screws from the Receiver
Module front panel and remove the four Phillips
screws. Remove the panel.
Step 4. Using the torque driver and deep-well socket, loosen
the three tension nuts on the adjustment screws.
Step 5. De-tune the preselector as follows:
Turn tuning screws 3 and 4 clockwise until they bottom
out. Be careful not to apply more than 3 in. – lb. of
torque to prevent warping the preselector cover and
housing.
Step 6. Connect the test equipment as shown in Figure 14.
Tuning Procedure
Step 1. Turn the station power supply ON (to provide the
active 50
Ω
termination).
Step 2. Adjust the signal generator to the frequency calculated
on page 39. Set the level to +5 dBm.
Figure 14 Test Equipment Setup for Preselector Field Tuning
From
Signal
Generator
RX
TX
Tension Nut
Tuning Screw
To Dip/Peak
Monitor
(RF Millivoltmeter
or Power Meter)
Tuning
Probe
To
Receiver
Board
To RX
Connector
on Top Panel
Preselector
Assembly
MAEPF-27040-O