Sharp FO-2150 Operation Manual page 198

Connections
Extension phone (optional)
If desired, you can connect an extension phone to the TEL. SET
socket on the fax.
To connect an answering machine to the Sharp Color MFP, see
Answering Machine Connection in Chapter 7 of your online
Operation Guide.
1
Remove the seal covering the TEL.
SET socket.
2
Connect the extension phone line to
the TEL. SET socket .
Important: In New Zealand, not all standard telephones and
answering machines will respond to incoming ringing when connected
to the extension socket of the equipment.
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