Motorola HAD4021A, Installation Manual

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2 Tuning Instructions for the HAD4022A Gain Antenna
Tuning Instructions for the HAD4022A Gain Antenna
The HAD4022A antenna must be trimmed in order to tune the antenna to cover the 132 – 174 MHz
frequency range. Perform the following to trim the antenna:
1. Remove the rod from the base of the antenna by unscrewing the two setscrews.
2. Cut the bottom portion of the rod, located below the ferrule, as per
“ Tuning Chart for
HAD4022A” on page 12
.
3. Re-insert the rod into the base of the antenna and secure by tightening the two setscrews.
4. Check the antenna and fine-tune it with an in-line watt meter, if a problem is suspected. Tune
for minimum reflected power at the frequency of interest and ensure the VSWR is less than
1.5:1.
FCC Requirements
Motorola Recommendations for Vehicle Roof-Top Antenna Locations
Recommended vehicle roof-top antenna installations are limited to metal body vehicles at the center
of the roof and center of the trunk deck locations. Refer to
Table 1 .
Additionally, the antenna installation must be in accordance with the following:
• Requirements of the antenna manufacturer/supplier
• Instructions in the radio installation manual
NOTE: To comply with RF Safety standards, HAD4021A and HAD4022A must only be mounted on
the roof.
To comply with FCC regulations when installing the antenna
lead-in cable,
DO NOT shorten the cable.
Advise the radio owner to unscrew the upper antenna assembly from the
base before entering an automatic car wash to prevent damage to the
antenna or roof of the vehicle. When unscrewing the antenna, be sure only
the upper section, not the locking nut, is removed. If the locking nut
becomes loose, retighten it securely against the mounting surface.
Table 1. Recommended Antenna Installation Locations
Vehicle Type Recommended Location
Standard metal passenger vehicles Center roof or center trunk lid
Vans, pickups, and other light trucks
(metal roofs) Center roof
Heavy duty equipment with metal roofs
(heavy duty trucks, semi-tractors, heavy
refuse trucks, cement mixer trucks) Center cab roof
Specialty vehicles (such as T-roofs, sun
roofs, or convertibles) Center trunk lid–recommended only for transmitter
output of less than 7 W
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