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HARRIS
888-9058-001
WARNING: Disconnect and lockout AC primary power prior to servicing
150
5.6.1.5 Sheet 6
The Analog Channel multiplexers is used to select and route to the Monitor board the
voltages and current samples from both power supplies and the outputs from the RF
peak detectors shown on Sheet 5. U41 is included to convert the selected signals to the
proper form for sending along the monitor bus, and K1 disconnects the bus from U4l
when control power is lost to the cabinet to prevent loading of the bus by the unpowered
circuits.
5.6.1.6 Sheet 7
This contains drivers and logic, which are custom-programmed PAL IC's. This circuitry
is used to automatically switch to alternate modes in some parallel-driver versions of
the transmitter.
5.6.1.7 Sheet 8
The Module-Enable circuits, also programmed by PAL IC's, which receive the TXD
and TXD* signals, the STSET* reset command, all MODF and PS SET signals and the
EXTINT* signal if external interlock is used. The PAL's contain the necessary logic to
turn the PA modules ON and OFF as commanded or if interlocked, and also to route the
STSET* pulse to the enable (EN) line for only those modules which are faulted.
5.6.1.8 Sheet 9
All power connections and the power bus protection.
5.7 Graphical User Interface
This is a basically a vendor display driven by an Intel hardware computer running a
version of Linux software. The only Harris built part is the interface board and it is only
for interconnection of cables. Drawing 843-5575-182 is included for reference in
troubleshooting the power supply output voltages or changing the hard drive.