Maintenance
5-4 HF SSB Transceiver 9323/9360/9390/9780 Technical Service Manual
Probe precautions
Observe the following when connecting CRO probes to the transceiver:
• When connecting probes to the PA assembly, the earth clip lead should be
wound around the body of the probe so that the earth clip just reaches the probe
tip. This reduces stray RF pick-up.
• The earth clip should be connected to the ground plane, adjacent to the point of
measurement.
• It is not advisable to connect two probes at the same time, particularly when
one is earthed to the PA ground plane and the other is earthed to the Exciter.
This may cause earth loop problems.
• Probes should be connected after power has been applied to the transceiver and
the test equipment. The earth connection should be made first and disconnected
last.
Surface mounted components
In the control head, surface mounted components are used extensively on the
printed circuit board. There are also a few fitted on other PCBs in the transceiver.
The removal or replacement of these components should only be attempted by a
skilled technician experienced in handling surface mounted components.