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Knowledge Base:  
FT-991 Repeater Offsets

Last Updated: 04/11/2016
The FT-991 is interesting in how it handles offsets.

1) There is one offset value per band that you can adjust. See menu items 80, 81, 82, and 83.

2) These are not the only offsets that the radio knows.

This radio has an "Auto offset" mode that you cannot configure. We know it's there because we work with the radio on a different level. This mode uses a predefined offset for the band. The definitions are based on the country of use and the band.

3) Now for how the radio works...

a) While working with memory channels you can change the offset frequency in the appropriate menu item for the band. If you don't press the RPT key while on a memory channel, that channel will use the "Auto offset" mode and shift based off the preset offset for the band that the radio has hard coded in its brain.

b) Once you press the RPT key, the channel will change to use the new offset frequency value. Also, you CANNOT get it to go back to Auto mode from the face of the radio. There is no keystroke to restore that ability.

So, you could have more than one offset for the memory channels. Two is your absolute maximum (one that the radio has preprogrammed and one that you set with the appropriate menu setting).

4) How this works for the programmer...

a) Enter your memory channel with the Offset Frequency and Offset Direction.

b) When you send the file to the radio, the programmer will set the memory channels up thusly...

Any that use the preset offset value that the radio knows for its Auto offset will be set to +/- just as you see them on the screen.

Any others will be set to DUP for Split operations. For these you will see the Receive (top) and Transmit (bottom) frequencies on the face of the radio. See page 103 of the Users Manual for the radio for more information about these channels. Hey guys... this is just like the splits that you see on your little VHF/UHF radios when the offset is non-standard. This same process can be used even if the offset is standard.

Why we do this... By setting the channel to Split, you are protected if you change the offset frequency for a new channel you are entering from the face of the radio. If we did not do this, all of these channels would change based on the new offset frequency... not a good thing for hitting a repeater that has not changed.

These channels may not look like they are working properly... but they are. Other than fooling the radio through use of the offset frequency and the preset frequency into using two different offsets, this is the best way to get the job done.

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