Performing Channel Changes - HP 8920A User Manual

Performing Channel Changes

Automated Test Software
Once a transmit channel is established, turn the Test Set's VOLUME up and
speak into your radio's microphone. You should hear your voice out of the Test
Set's speaker. Access the DUPLEX TEST screen to display the transmitter's
power and frequency error.
Testing the mobile's ability to change to other receive channels when commanded
requires rapid RF Generator frequency changes. After the idle message on the
home channel has been established (using Message 1), a message is sent to change
channels (Message 2). The mobile must see the LTR-encoded carrier at the new
channel frequency within a few seconds to establish the new channel. You can
change the RF Generator's frequency using a global USER key after entering an
increment value equal to the required channel offset. This procedure must be done
very quickly to work.
The best way to perform a channel change is to use an HP-IB or IBASIC program
to change the RF Generator's frequency to the new channel frequency
immediately after the appropriate message has been output.
Hewlett-Packard offers software packages to test your LTR-format trunked radio
in a fraction of the time normally required for manual testing. You can choose any
combination of tests, from full transmitter and receiver testing, to a single test.
The software is shipped on a memory card that inserts directly into your Test Set,
and it comes with complete documentation and a blank SRAM memory card for
storing your test procedures and test data.
Chapter 10, Signaling Encoder (AF Generator 2)
Using the LTR Encoder
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