Motorola F2265A, Owner'S Manual

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1-1
CHAPTER 1
DESCRIPTION
1.1 GENERAL DESCRIPTION
The HF-SSB Automatic Antenna Tuner Unit (ATU)
model F2265A is an antenna matching network that
provides efficient RF power transfer from the radio
system to the antenna.
The ATU handles up to 125 watts Peak Envelope
Power (PEP). It is used for voice and Continuous
Wave (CW) Morse code communications.
ATU F2265A matches the antenna impedance to the
50
Ω output impedance of the radio system, with a
nominal VSWR of 1.5 in the 1.6 to 30 MHz frequency
range.
The ATU is housed in a weatherproof case, allowing
outdoor installation, such as open roofs.
1.2 FUNCTIONAL DESCRIPTION
The F2265A Automatic Antenna Tuner (ATU) operates
in the 1.6 to 30 MHz frequency range at 125 watts peak
envelope power (PEP). The ATU automatically selects
the network component for the antenna matching, thus
eliminating the need for programming, presetting,
manual tuning and adjustment during the installation
and the operations.
A microprocessor circuit checks the antenna matching
each time the channel is changed and then
automatically switches inductors and capacitors in and
out of the matching network. The tuning data for a
given channel is stored in a memory and kept as long as
the ATU is on. The next time the channel is used, the
stored tuning data for that channel is used, considerably
reducing the tuning time (provided that the VSWR is
within the specified limits).
Figure 1-1. ATU General View
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