HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual 5-1
5 Maintenance
This chapter provides maintenance and fault finding procedures that can be carried
out on the 9323, 9360, 9390 or 9780 transceiver. It covers general warnings and
cautions to be observed when working with electronic equipment.
This chapter also outlines fault finding steps when receive and transmit failures
occur and provides removal and installation procedures.
General
CMOS devices
A number of Complementary Metal Oxide Semiconductor (CMOS) devices are
used in the transceiver and most of them have built-in protection. However, their
extremely high open-circuit impedance makes them susceptible to damage from
static charges. Care must therefore be used when shipping and handling the
devices and servicing the equipment in which they are installed.
Packaging
Replacement CMOS devices are supplied in special conductive packaging. They
should remain in this packaging until required for use.
Switching off
Ensure that power supplies are switched off before making connections or
disconnections between circuit boards.
Handling
Handle circuit boards and touch conductive parts as little as possible.
Grounding
Anything connected to or touching the circuit board tracks should be grounded as
follows:
• Ground test equipment connected to a board through its mains lead.
• Discharge static charges, which may build up on a person, by touching a
grounded metal surface with both hands. This should be done before working
on, and at frequent intervals while working on circuit boards.
• Wear a suitably grounded conductive wrist strap. This will minimise the build
up of static on you.
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