Yaesu FC-757AT, Инструкция по эксплуатации

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THE FC-757AT
FULLY AUTOMATIC HF ANTENNA TUNER
The FC-757AT is a multi-functional microprocessor-controlled RF handling device designed to
provide for all of the antenna switching, impedance matching and RF metering requirements of
an
amateur station, with maximum power handling capability of 150 watts.
Designed to match the FT-757GX All Mode HF Transceiver, which provides automatic band­
switching and power control functions via the supplied control cable, the FC-757 AT can also be
automatically controlled by the FT-980 Transceiver via an optional control cable. Manual power
and bandswitching controls are also provided for use when the FC-7 57 AT is powered by an
independent DC source and used with any other HF transceiver, transmitter or receiver.
The 4-bit microprocessor allows for fast, accurate automatic impedance matching utilizing a
modified pi-L network. A directional CM coupler at the transmitter side of the network and an
RF pickup at the antenna side ensure a wide range of SWR acceptance, and final SWR to the
transmitter better than 1. 5: 1 for impedances in that range. Manual matching is also possible for
particularly difficult situations, or when matching for receiving only.
Two antenna jacks are provided, along with controls for remote automatic and manual selection
of up to five antennas in total when the FC-757AT is used with the optional FAS- l -4R Remote
Antenna Selector. An internal 50-ohm dummy load is included in the FC-757AT, along with an
in-line RF wattmeter and a self-calculating (automatic) SWR meter.
The particular antenna selected for operation on a particular band, along with the settings of the
matching network, are digitally encoded and stored in lithium-backed RAM by the micro­
processor, so that when that band is selected again, the same antenna and matching settings are
automatically reset quickly. Thus no extra time is required for rematching.
During operation, any change in frequency that causes the SWR to rise above 1. 5: 1 will cause
the auto-tune system to automatically rematch the load if desired, and the new settings will
then be automatically written into memory for that band.
Please read this manual carefully before operating your FC-7 57 AT, to ensure optimum
performance and enjoyment of its many features.
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