Testing Cellular Mobiles - Motorola R2008C Operator's Manual

3.0 TESTING CELLULAR RADIOS
To ensure satisfactory operation of the cellular radio, the
transceiver controller function, the digital and analog signaling
functions, the transceiver operation, and the information
contained in the Number Assignment Module (NAM) must be
verified. Since the transceiver functions are handled by a
microprocessor based controller, the first functional block to be
checked must be that controller. Most radios, and especially
AMPS compliant radios, perform a basic self test of the radio
when first powered up. If the self test is successfully
completed, the handset indicators are activated. If the
controller is not working, the indicators will either not
activate or will activate in an abnormal manner. A faulty
controller will probably prevent further troubleshooting until it
is either replaced or repaired.
Once past the self test, the cellular radio will attempt to
locate a forward control channel (FOCC). At this point the
R2008C can be used to supply the FOCC signal modulated with the
appropriate overhead control messages as a cell would on its data
channel.
A
cradle 'no service' indicator will extinguish when
the radio has successfully tuned to, decoded and responded to the
FOCC signal.
A failure at this portion of the sequence would most
likely indicate that the receiver or the receiver/controller
interface circuitry has failed.
The manual test mode of the R2008C, which allows separate control
and monitoring of the receiver, transmitter, and controller
status, can be used to isolate the source of the failure.
With the cellular radio in service, either the call origination
or the call reception capability of the radio can be checked.
With the R2008C, the signaling exchange necessary to execute
both sequences can be generated with the proper responses
automatically checked for accuracy. Error messages are
provided in the event that the radio does not respond pro-
perly. These messages and the manual test capability can
then be used to isolate the cause of the failure.
Failure at this point would most likely be in the trans-
mitter or data generating circuitry as the receiving circuitry
had to be working to get an 'in service' indication.
A successful call origination or call reception test will end
with the radio on a voice channel. On the voice channel
the radio detects and checks for the correct SAT frequency,
and then transponds the SAT signal on the reverse voice
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