Panasonic KX-T4300BA - Manual (Page 28)

Advanced operation
Other features
CH Button
FLASH Button
Selecting the clearest channel
A channel is a selected set of receiving and transmitting frequencies.
You may select the clearest one of the 5 available channels.
If you hear interference noise while
having a conversation, press the CH
button.
—Each time you press the CH button,
the next channel is selected. Press
the CH button repeatedly until the
clearest channel is selected.
—The selected channel number is
displayed on the Call-Counter.
^9ote:
—If the portable handset user is too far from the base unit, the CH
button does not function fully. Approach the base unit.
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