Automatic Antenna Tuner Operation; Antenna Tuner Memory System - Yaesu FT-897 Operating Manual

FC-30 A
The optional FC-30 Automatic Antenna Tuner provides au-
tomatic tuning of a coaxial line so as to present a nominal
50 Ω impedance to the FT-897's HF/50 MHz antenna port.
Before operation can begin, you must instruct the FT-897's
microprocessor that the FC-30 is being used. This is done
using the Menu Mode:
1. Press and hold in the [ F ] key for one second to activate
the Menu mode.
2. Rotate the MEM/VFO CH knob to recall Menu Mode
No-001 [ EXT MENU ] , then rotate the DIAL to change
the setting to "ON" to enable the extended Menu Mode.
3. Rotate the MEM/VFO CH knob to recall Menu Mode
No-020 [ CAT/LIN/TUN ] . The default setting for this
Menu is "CAT." Rotate the DIAL to change the setting to
"TUNER."
4. Press and hold in the [ F ] key for one second to save the
new setting and exit, then turn the transceiver off.
5. Set up the FC-30 and FT-897 per the illustration, then
turn on the transceiver's power again. Do not set up
the FC-30 and FT-897 before changing the Menu
Mode, item No-020 [ CAT/LIN/TUN ] .
6. Press and hold in the [ F ] key for one second to activate
the Menu mode.
7. Rotate the MEM/VFO CH knob to recall Menu Mode No-
085 [ TUNER/ATAS ] . The default setting for this Menu is
"OFF." Rotate the DIAL to change the setting to "TUNER."
8. Press and hold in the [ F ] key for one second to save the
new setting and exit.
Operation is similar to the procedure for the ATAS-100/-120:
1. Press the [ F ] key, as needed, to recall Multi Function
Row "k" [ TUNE, DOWN, UP ] .
2. Press the [ A ]( TUNE ) key to turn the FC-30 on. "Paren-
theses" will appear on both sides of the "TUNE" indica-
tion, and the "TUNE" will appear on the LCD.
3. Press and hold in the [ A ]( TUNE ) key to initiate automatic
tuning. The FT-897 transmitter will be activated, a car-
rier signal will be sent out, and the coils and capacitors in
the FC-30 will be selected/adjusted for optimum SWR.
When tuning is complete, the transmission will cease, and
you will be ready for operation on this frequency.
Tuning data will be stored in the FC-30's
Memory system. See the discussion below for
details on how this works.
Control Cable
IN PUT
G ND
22 A
ACC
DATA
FT-897 O M
PERATING ANUAL
UTOMATIC
To 144MHz/ 430MHz Antenna
To HF/50MHz Antenna
KEY
ANT
Supplied
Coaxial Cable
T
RANSMITTER
A T
NTENNA UNER

Antenna Tuner Memory System

The FC-30, working in concert with the FT-897, can store
impedance matching data in its micro-computer memory, so
as to provide instant adjustment as you transmit in different
areas of a particular band. A total of 100 memories are pro-
vided: 11 of these are "general" memories apportioned one
per band, while the remaining 89 are allocated for specific
frequency data within the various bands, with the capability
to resolve new tuning data every 10 kHz. A few guidelines
should be noted regarding the FC-30's memory system:
Tuning data is stored when you make an active effort to store
it by pressing and holding in the [ A ]( TUNE ) key for one
second. Although the tuner will automatically activate itself
if it encounters more than 1.5:1 SWR, this memory will not
be stored unless you have pressed the [ A ]( TUNE ) key for
one second. This allows you to store your favorite operating
frequency areas into tuner memory without tying up memory
space with matching data on seldom-used frequencies.
If the FC-30 cannot resolve a satisfactory match because
the SWR is above 3:1 (2:1 on the 50 MHz band), the tuning
process will stop, and no memory data will be stored. How-
ever, you may wish to move frequency a few kHz, then press
the [ A ]( TUNE ) key again for one second, as slight changes
in the reactance may allow a match to be obtained. Then go
back to the original frequency and try again.
Another technique which may allow matching in some situ-
ations is to add a few feet or meters of coaxial cable on the
"antenna side" of the FC-30. This will change the imped-
ance transformation taking place in the coaxial cable, possi-
bly moving the impedance presented to the FC-30 into an
acceptable range. Note that this is not changing the actual
antenna SWR, but only the impedance "seen" by the FC-
30's matching circuits.
If your antenna system presents an SWR of less than 1.5:1,
you may wish to turn off the antenna tuner, as full transmit-
ter power will be delivered to the antenna system without
intervention by the FC-30.
If the impedance encountered by the FC-30 exceeds 3:1,
and the "HI SWR" icon is illuminated, the microprocessor
will not retain the tuning data for that frequency, as the FC-
30 presumes that you will want to adjust or repair your an-
tenna system so as to correct the high SWR condition.
O
PERATION
O
PERATION
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