Kenwood TM-251A Instruction Manual page 99

In general, the status of functions on the Display apply to
the Main Band and not the Sub-band as long as Full
Duplex is selected. That is, the status of functions
applies to the Transmit band. One exception is when
[F], [REV] is pressed. This allows you to receive on the
Main Band as indicated by the Sub-display changing to
the same frequency as the Main Band. However,
pressing [PTT] immediately restores the Sub-band
frequency on the Sub-display.
Certain functions cannot be used if Full Duplex is
activated. The following chart identifies these functions:
Non-functional Pade Non-functional
with Full ee with Full
|__Duplex ON | ON Duplex ON
| Programmable | | Channel Display
Band Scan Limit
Select
Programmable Display Mode
VFO Limit Select | 33 |
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