Installation Planning And Procedures; Testing And Maintenance; Power Protection Circuitry - Motorola MaxTrac 100 Operating Instructions Manual

Installation Planning and Procedures

Testing and Maintenance

Your MaxTrac radio is completely adjusted, tested, and inspected before
shipment. However, FCC regulations state that a station license must be obtained
for each radio installation (radio or base) by the owner of the equipment. The
station licensee is responsible for ensuring the transmitter power, frequency, and
deviation are within the limits permitted under the station license.
No technician's license is required for installing and maintaining radio equipment.
However, the frequency and deviation of the transmitter must be checked on
installation and at least once yearly.

Power Protection Circuitry

The radio you are installing has been tested for proper transmitter power output
before leaving the factory. Each radio is set to the proper output power level while
connected to an accurate 50-ohm load impedance. Once the power level has
been set, the internal power control/protection circuitry will reduce the power
output whenever it senses a load impedance significantly different from 50 ohms.
This protection circuitry significantly enhances the radio's reliability with minimal
performance degradation.
If you check transmitter output power levels during installation, be sure you are
using a good 50-ohm load, with a minimum of adapters and using short test
cables. Any load variation from 50 ohms may cause an apparent reduction in
output power due to the normal operation of the control/protection circuitry.
These variations in power with other than 50-ohm load impedance will be most
pronounced in the 800MHz and 900MHz bands since cables, meters,
connectors, etc. have larger effects in those bands. However, the factors are still
significant at UHF and VHF and considerable care should be exercised at these
frequencies. If output power seems to be unusually low (greater than can be
explained by the normal calibration differences you experience), check your test
setup. If output power goes up as you improve the quality of the load impedance
(be sure to de-key when making any changes in load), the control/protection
circuitry is performing normally.
Typical mismatches in the load impedance (greater than 1.2:1 VSWR [voltage
standing-wave ratio]) may result in a 10-20% variation in the actual measured
power output. Within these limits, the radio operates normally, and you should not
attempt to service it.
Installation Planning and Procedures 23
Testing and Maintenance /
Power Protection Circuitry