674740
64
Zoom out
Zoom in
Previous page
1/154
Next page
Page 62
FT-991 OperaTing Manual
About Atu operAtion
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 “
HI-SWR
” icon has appeared. The operator presses and holds
in the
TUNE
button for one second 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 imped-
ance 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 2:1
The tuner settings are stored in the ATU memory.
SWR (After tuning) Greater than 2:1
Tuning data will not be retained in memory. If you return to the same frequency, 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 memorized. Please investigate
the high SWR condition and resolve the problem before attempting further operation using this antenna.
usinG the autoMatic antenna tuner
Figure 1
Figure 2
Feed Point SWR
SWR: 3.0
Retuned Setting
Memorized ATU Tuning
The “HI-SWR” icon appears on the display
when you transmit on the frequency
SWR after ATU Tuning
Frequency
Frequency
64


Need help? Post your question in this forum.

Forumrules


Report abuse

Libble takes abuse of its services very seriously. We're committed to dealing with such abuse according to the laws in your country of residence. When you submit a report, we'll investigate it and take the appropriate action. We'll get back to you only if we require additional details or have more information to share.

Product:

For example, Anti-Semitic content, racist content, or material that could result in a violent physical act.

For example, a credit card number, a personal identification number, or an unlisted home address. Note that email addresses and full names are not considered private information.

Forumrules

To achieve meaningful questions, we apply the following rules:

Register

Register getting emails for Yaesu FT-991 at:


You will receive an email to register for one or both of the options.


Get your user manual by e-mail

Enter your email address to receive the manual of Yaesu FT-991 in the language / languages: English as an attachment in your email.

The manual is 30,58 mb in size.

 

You will receive the manual in your email within minutes. If you have not received an email, then probably have entered the wrong email address or your mailbox is too full. In addition, it may be that your ISP may have a maximum size for emails to receive.

The manual is sent by email. Check your email

If you have not received an email with the manual within fifteen minutes, it may be that you have a entered a wrong email address or that your ISP has set a maximum size to receive email that is smaller than the size of the manual.

The email address you have provided is not correct.

Please check the email address and correct it.

Your question is posted on this page

Would you like to receive an email when new answers and questions are posted? Please enter your email address.



Info