Sharp FO-2150 Operation Manual page 149

Option Settings
Setting 2: NUMBER OF RINGS TO ANSWER
This sets the number of rings the fax machine waits before answering
an incoming call in FAX and TEL/FAX reception modes. Enter any
number from 2 to 4.
Initial setting: 4
Enter a number
from 2 to 4
Setting 3: 4 RINGS TEL ANSWER
Press 1 (YES) to have the machine answer a call after 4 rings when it is
in TEL reception mode. Press 2 (NO) to turn the function off.
Initial setting: 2
Press
NO
YES
or
9-2
until
display
NUMBER OF RINGS
Press
shows:
4 RINGS TEL ANS.
until
4 RINGS TEL ANS.
display
shows:
TEL/FAX REMOTE #