HP 8924E, Assembly

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Chapter 1, Introduction
Theory of Operation
N:\mkt\MANUALS\HP8924C\ALR\intro.fb
Theory of Operation
The Test Set is primarily an RF transceiver that operates in the 30 to 1000 MHz
range, and a group of instruments that analyze received signals. Several
modulation sources are available for testing a variety of cellular phones and other
types of radios. A modulation analyzer is used to measure various parameters on
the received signal from the radio-under-test. The oscilloscope and spectrum
analyzer provide additional received signal analysis.
The following information is very general. Refer to Chapter 9, Block Diagrams,
for detailed drawings for each assembly.
Internal
Operating System
A 68020 microprocessor acts as the “host” processor of the Test Set. It receives
commands from the front-panel controls and communicates directly with almost
every assembly inside the Test Set. The host is also in constant communication
with several other microprocessors located in assemblies throughout the Test Set.
Communications to the HP-IB, Serial, and Parallel ports are through the Control
Interface (A33) assembly to the host processor.
This processor is also the core for the internal IBASIC computer. The IBASIC
computer is used to load and run various software packages for automated radio
tests. It is also responsible for executing the internal diagnostic routines used to
troubleshoot a failing instrument.