Terrasat Rx 1+1, Operation Manual

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Functional Description
RF Signal Flow
The RF signal flow is the same whether the unit is AC powered or DC powered.
L-band inputs to the Rx 1+1 interface module are through the input connectors J5 (for
the A: side LNB) and J4 (for the B: side LNB). The online signal is selected through
an RF switch (relay) and routed to the J6 connector (L-band Rx output) through the
mux/de-mux circuitry. Samples of both L-band inputs (from the A: side and B: side
LNBs) are detected and sent to the M&C (monitor and control) card for monitoring
purposes. The 10 MHz reference signal is demultiplexed and then detected.
Information about the 10 MHz signal is then sent to the M&C card for alarm
processing. The internally generated DC supply (+18 VDC) and the 10 MHz reference
signal are multiplexed to the L-band signal to feed both LNBs through the J4 or J5
connectors. Before multiplexing the DC voltages, the current and voltage that are fed
to the LNBs are detected and the information is sent to the M&C card.
The M&C card also controls and monitors both waveguide and relay switches. The
connection to the waveguide switch is through the J7 connector.
LED Indicators
The Rx 1+1 interface module has a bank of LEDs that provide quick visual indicators
of system status. Indicators include power, Ethernet activity, system status, mode of
operation, and alarm status. LED colors signify the following:
• Flashing green – No alarms
• Flashing Red – Minor alarm being reported
• Steady Red – Major alarm being reported
The LEDs are identified in Figure 3.12 on page 3-16 .
Emergency Switches
The Rx 1+1 interface module offers two switches that enable you to switch from the
A: side system to the B: side system when the M&C card is no longer able to control
the switch. Use the SW1 switch to change the mode of operation from normal
(controlled by the M&C card) to emergency (manually controlled by the user). Use the
SW2 switch to change from the A: side unit to the B: side unit (or vice versa). You
must first activate SW1 to be able to see the results of activating SW2.
Note:
When in emergency mode, the LED labeled “Normal/Emergency” will turn from
green to red. When you return to normal mode, the LED will turn green. The LED
must be green in order to enable remote control of the waveguide switch.