Sony IT-A300: Operating Instructions Manual page 21

Some services require you to
use touch-tone. This is not a
problem if your phone already
uses tone dialing. If your phone
uses pulse dialing, however,
you need to follow the steps
below to use these services.
1
VANE tn wa oR ag EE
TONE (%) key
Use the phone to dial the service number.
NO
You only need to press TONE
once to turn dialing to tone; this
will remain effective until the call 3
is disconnected.
Press the dialing keys as required.
Using as a telephone | 21
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