Depaepe HD Max Mode D'emploi page 11

Note : if the "amplify switch" located under the telephone is in the
"ON" position, pressing " " key is not necessary.
Amplify switch
When the Amplify switch (located under the base) is in the
"MANUAL" position, the receive speech boost will be canceled at
the end of each conversation, when hanging up the handset.
The "MANUAL" mode is convenient when different users,
hearing impaired or not, use the same HD MAX telephone;
activating manually this feature, on demand, by pressing the
" " key minimizes potential acoustic shocks.
However, if the HD MAX should always be used with the receive
boost on, then the Amplify switch should be in the "ON" mode ; this
way, the amplification boost will always be active even after each
hanging up of the handset.
BIS/P (LNR REDIAL/PAUSE)
This key allows the last number dialed to be automatically redialed
(maximum capacity is 32 digits).
Pressing this key when dialing enters a timed pause in the dialing
process: this may be useful when storing a number into a memory
key (see "Storing a Telephone number" section).
ATT
When pressing this key during a call, the other party will be put on
hold (with music while on hold). The handset can be hung up and a
red led will light to alert someone is on hold. To resume the
conversation, simply pick up the handset.
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