Panasonic KX-TGM420 Operating Instructions Manual page 52

3 [
• If you select "Custom tone", select the
desired type.  [OK]
• The selected setting is shown on the handset
display while talking.
Base unit
1 Press and hold [TONE] for about 2 seconds while
talking.
2 Press [+] or [–] repeatedly to select the desired
setting.
The selected setting flashes on the message
•
counter while talking.
3 To exit, press [TONE] or wait for about 5 seconds.
Note for handset and base unit:
• The selected setting is applied immediately and is
also used for future calls.
• Depending on the condition and quality of your
telephone line, this feature may emphasize existing
line noise. If it becomes difficult to hear, reset to the
default setting (Tone 2).
52 | P a g e
]: Select the desired setting.  [OK]