*
FAIL LED-shows red after a test if there are failures
*
PUSH TO TEST switch -push this switch to start a test of the RFU.
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SATCOM SYSTEM -RADIO FREQUENCY UNIT
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SATCOM SYSTEM -ATTENUATOR
Purpose
The attenuator adjusts the radio frequency signal level to make the output from the RFU compatible to the input level needed for the HPA.
Physical Description
The attenuator has these properties:
*
Length -2 inches
*
Diameter -.5 inches
*
Weight -1.3 ounces.
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SATCOM SYSTEM -ATTENUATOR
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SATCOM SYSTEM -BEAM STEERING UNIT
Purpose
The beam steering unit (BSU) points the radio frequency signals at the satellite.
Physical Description
The BSU has these properties:
*
Length -14 inches
*
Width -10 inches
*
Height -4 inches
*
Weight -18 pounds.
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SATCOM SYSTEM -BEAM STEERING UNIT
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SATCOM SYSTEM -LOW NOISE AMPLIFIER/DIPLEXER
Purpose
The low noise amplifier/diplexer (LNA/DIP) is a filter and an amplifier. It lets the SATCOM system receive and transmit signals at the same time. It also increases the strength of received low level satellite signals.
Physical Description
The LAN/DIP has these properties:
*
Length -11 inches
*
Width -7.8 inches
*
Height -2 inches
*
Weight -6.6 pounds.
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SATCOM SYSTEM -LOW NOISE AMPLIFIER/DIPLEXER
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SATCOM SYSTEM -HIGH POWER AMPLIFIER
Purpose
The class A high power amplifier (HPA) increases the signal strength of transmit signals to the SATCOM antennas by as much as 40 watts for multiple channels or 80 watts for a single channel for a short time.
The class C HPA increases the signal strength by as much as 40 watts.
Physical Description
The class A HPA is an 8 MCU LRU and weighs 32 pounds. It has these front panel controls and indicators:
*
PASS LED -shows green after a test if there are no HPA failures
*
FAIL LED -shows red after a test if there are HPA failures
*
PUSH TO TEST switch -push this switch to start a test of the HPA.
The class C HPA is a 4 MCU LRU and weighs 15 pounds.
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SATCOM SYSTEM -HIGH POWER AMPLIFIER
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SATCOM SYSTEM -RADIO FREQUENCY COMBINER
Purpose
The radio frequency combiner (RFC) permits the SATCOM system to operate with more than one antenna. The RFC gets receive signals from the low noise amplifiers/diplexers (LNA/ DIPs). The RFC sends the received signal to the radio frequency unit (RFU).
Physical Description
The RFC has these properties:
*
Length -2.00 inches
*
Width -1.75 inches
*
Height -0.75 inches.
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SATCOM SYSTEM -RADIO FREQUENCY COMBINER
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SATCOM SYSTEM -RADIO FREQUENCY SPLITTER
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