Using The Automatic Antenna Tuner; Peration - Yaesu FT DX 1200 Operation Manual

U
SING THE
Figure 1 depicts a situation where normal tuning via the TU has been successfully completed, and the tuning data has
been stored in the TU memory. The antenna system as seen by the transmitter is shown.
In Figure , the operator has changed fre uency, and the "HI-SWR" icon has appeared. The operator presses and holds
in the [ TUNE ] button for two seconds to begin impedance matching using the TU.
If a high SW condition exists above 3 1), corrective action must be taken in the antenna system to bring the imped-
ance closer to 0 hms. The TU will refuse to memori e settings on fre uencies where the SW exceeds 3 1.
SW may indicate a mechanical failure in the feed system, and can lead to the generation of spurious signals causing
TVI, etc.
Frequency
Memorized ATU Tuning
Frequency
SWR (After tuning) Less than 1.5:1
The tuner settings are stored in the TU memory.
SWR (After tuning) Greater than 1.5:1
Tuning data will not be retained in memory. If you return to the same fre uency, the tuning process must be re-
peated.
SWR (After tuning) Greater than 3:1
The "HI-SWR" icon will light up, and the tuner settings, if achieved, will not be memori ed. lease investigate
the high SW condition and resolve the problem before attempting further operation using this antenna.
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A
UTOMATIC
A ATU O
BOUT
Feed Point SWR
SWR after ATU Tuning
F
F
About ATU Memories
A
NTENNA

PERATION

1
IGURE
The "HI-SWR" icon appears on the display
when you transmit on the frequency
SWR: 3.0
2
IGURE
FT
DX
T
UNER
Retuned Setting
1200 O M
PERATING ANUAL
High