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Make sure test equipment being used has a correct earth on its mains lead.
Before and during work on PCB's or handling CMOS devices, discharge static charges, which may build up
on a person, by touching a grounded metal surface with both hands. If possible wear a suitably grounded
conductive wrist strap.
Transmitter power amplifier maintenance precautions
When making measurements of the low level stages of the exciter, it is advisable to remove the drive
to the PA and Filter PCB; this can be achieved by unplugging the coaxial cable from the RF/Audio PCB to
the PA. If working on the whole system with the power amplifier connected, caution should be exercised
when connecting probes in the input area of the PA board as a probe can cause instability which can drive
the power amplifier to full power without ALC action being available resulting in damage to the power
amplifier. When connecting probes to the PA assembly, the earth clip lead should be wound around the
body of the probe and the earth clip should be connected to the ground plane, adjacent to the point of
measurement to which the probe tip is connected, thus reducing any stray RF pick-up.
