Panasonic KX-TGM420 Operating Instructions Manual page 51

Handset
You can select a tone control setting while talking on
the phone.
There are two methods available.

Using the [TONE] key
1 Press [TONE] on the side repeatedly to select
the desired setting while talking.
2 To exit, press [BACK] or wait for a few
seconds.
• The selected setting is shown on the handset
display while talking.
Note:
• To select one of the "Custom tone" settings, follow
the instructions in "Using the [MENU] key", page
51.

Using the [MENU] key
1 Press [MENU] while talking.
2 [ ]: "Tone control"  [SELECT]
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