Instruction Manual

Table Of Contents
5.9.2.2
Preparing the Equipment for UHF Alignment
Perform the following procedure to prepare the equipment for UHF alignment.
Procedure:
1 Ensure the
base radio (with preselector assembly) is installed in a functional station cage
equipped with a power supply module.
2 Using the torque driver and deep well socket, loosen the three tension nuts on the adjustment
screws.
3 Detune the preselector by turning 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 preselector cover and
housing.
4 See Figure 60: Preselector Tuning — UHF on page 165.
5.9.2.3
Tuning The UHF Preselector
NOTICE: When tuning for peak or dip, turn the tuning screw 1/2 turn past the peak or dip to
verify that you have obtained a true peak or dip. After you have found true peak or dip, turn the
screw back to the location of the original peak or dip.
See the figure for the location of the tuning screws and cavity probe holes.
Figure 60: Preselector Tuning — UHF
Procedure:
1 Turn the power supply ON (to provide a 50 Ohm termination).
2 Adjust the signal generator to the frequency calculated in Calculating The UHF Alignment
Frequency For a Single Receive Frequency on page 164 or Calculating the UHF Alignment
Frequency for Multiple Receive Frequencies on page 164. Set the level to +5 dBm.
3 Insert the tuning probe into cavity U2 and adjust tuning screw 2 for a PEAK.
MN003286A01-H
Chapter 5: GTR 8000 Base Radio Optimization
165