Yaesu FT-950, Руководство по эксплуатации, Страница: 61 / 132

Page 59 FT-950 O
PERATING
M
ANUAL
A
BOUT
ATU O
PERATION
Figure 1 depicts a situation where normal tuning via the ATU has been successfully completed, and the tuning data has been
stored in the ATU memory. The antenna system as seen by the transmitter is shown.
In Figure 2, the operator has changed frequency, and the “ ” icon has appeared. The operator presses and holds in
the [ TUNE
] button for two seconds to begin impedance matching using the ATU.
If a high SWR condition exists (above 3:1), corrective action must be taken in the antenna system to bring the impedance
closer to 50 Ohms. The ATU will refuse to memorize settings on frequencies where the SWR exceeds 3:1. A High SWR
may indicate a mechanical failure in the feed system, and can lead to the generation of spurious signals causing TVI, etc.
About ATU Memories
SWR (After tuning) Less than 1.5:1
The tuner settings are stored in the ATU memory.
SWR (After tuning) Greater than 1.5:1
Tuning data will not be retained in memory. If you return to the same frequency, the tuning process must be repeated.
SWR (After tuning) Greater than 3:1
The “ ” icon will light up, and the tuner settings, if achieved, will not be memorized. Please investigate the
high SWR condition and resolve the problem, before attempting further operation using this antenna.
U
SING THE
A
UTOMATIC
A
NTENNA
T
UNER
SWR: 2.0
Frequency
SWR: 1.5
Feed Point SWR
SWR after ATU Tuning
SWR: 1.0
F
IGURE
1
F
IGURE
2
SWR: 3.0
SWR: 3.0
Frequency
SWR: 2.0
Memorized ATU Tuning
Retuned Setting
SWR: 1.0
The “ ” icon appears on the display
when you transmit on this frequency