| DIRECT
DIGITAL FREQUENCY SYNTHESIS |
| Two direct
digital synthesisers (DDSS) and a magnetic rotary
encoder provide silent, silky-smooth tuning, pure local
signals and very fast transmit/receive switching.
Frequency accuracy and stability are assured by driving
both DDSs from a single master oscillator, and the
optional TCXO-4 temperature-compensated crystal
oscillator is available for enhanced ±2-ppm stability
from -10 to +50C. |
| TWO
AUTOMATIC ANTENNA TUNERS |
| A choice of
two automatic antenna tuners is available for the
FT-840, each with its own microprocessor and memories
which automatically store most recent antenna matching
settings for nearly instant recall while changing
operating frequency. The matching FC-10 can be mounted
right next to the transceiver, or the FC-800 can be
installed remotely at the antenna feed point. Each
antenna tuner is controlled from the FT-840 front panel. |
| CLEAN
TRANSMITTER OUTPUT |
The digitally
synthesised local signals ensure clean, low-noise
transmitter output: up to 100 watts on all HF amateur
radio bands in CW, SSB and FM* modes, and up to 25 watts
carrier in AM mode.
*FM operation
requires optional unit. |
| WIDE
RECEIVER DYNAMIC RANGE |
| The receiver
tunes all frequencies between 100 kHz and 30 MHz in
10-Hz steps. For clear weak-signal work, the low-noise,
high-performance receiver front-end feeds an active FET
balanced mixer. A 12-dB attenuator can be inserted in
the receiver front end for clear copy of even very
strong signals. |
| FC-10
& FC-800 REMOTE AUTOMATIC ANTENNA TUNER OPTIONS |
Both the
FC-10 and FC-800 provide all-band transmitting
capability with an end-fed random wire or long whip
antenna (the FC-1 0 antenna tuner should be used with
antennas requiring coaxial feed line, such as beams).
Both tuners make use of the control circuitry built into
the FT-840, which allows the operator to control and
monitor automatic operation of the FC-10 or FC-800
mounted near the antenna feed point. The FC-10 provides
a compact, easy-to-install unit that is styled to match
the appearance of the FT-840. For more demanding
applications, the FC-800 uses specially selected
thermally stable components and is housed in a
waterproof casing to reliably withstand severe climatic
extremes.
Both the FC-10 and FC-800 match a wide variety of
antennas to within a 1.5:1 SWR on any amateur band
frequency in typically less than 30 seconds. Transmitter
power required for matching can be as little as 10
watts, and matching settings are automatically stored in
memory for instant |
