Brother 1840C - Manual (Page 44)

SETUP SEND 3 - 2
One-Touch dialling
Press the One-Touch Key of the location you want to call.
(See Storing One-Touch Dial numbers on page 5-1.)
To dial One-Touch numbers in the black square, hold down Shift as
you press the One-Touch Key.
Speed-Dialling
Press Search/Speed Dial , # , and then the two digit Speed-Dial
number. (See Storing Speed-Dial numbers on page 5-2.)
If the LCD shows Not Registered when you enter the
Speed-Dial number, a number has not been stored for it.
two-digit number