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BARRETT 4075 LINEAR AMPLIFIER - OPERATING & INSTALLATION MANUAL
Antenna Connection
The 4075 system can only perform well when a suitable antenna, in good
condition, is installed. There are many antenna types available on the market,
and so no specific antenna detail is provided in this manual. Please refer to the
instruction brochures for the antenna type selected. Please note that a VSWR of
< 2:1 is desirable for optimum performance of the Linear Amplifier.
We suggest that for high power transmitters, a type RG-213 or better cable
is used for all coaxial feeds beyond the Linear Amplifier. For improved coaxial
feeder performance over long runs, we suggest the use of a low-loss coax-
ial cable. Our Technical Services department can assist with cable selection if
required. The use of a lightning protection module is recommended.
Fitting the Linear Amplifier
Unpack the Linear Amplifier and refer to the connection diagrams shown
below. Unless otherwise specified for special project requirements, all cabling
with the exception of the coaxial RF output cable, are installed in the rack and
so identification and connection is straightforward.
Both the 4075 Linear Amplifier and the 4075 Power Supply units have been
factory adjusted for optimum performance.
4050 Transceiver Setup
Important: The 4050 Transceiver must be specifically set for use with a Linear
Amplifier. It is important that the “Antenna Type” selected within the “I/O Set
-
tings” menu of the Transceiver, is set to “4075 Linear Amplifier”. In this mode,
the output power of the Transceiver is limited to between 30 W and 80 W, and
the Automatic Level Control (ALC) voltage is sourced from the Linear Amplifier.
Please refer to the 4050 HF SDR Operating and Installation Manual (P/N
BCM40500) for comprehensive details on operating the Transceiver.