The AC-701 can be used as a telephone adaptor for Encore PL system.  When used as telephone adaptor, the unit must work in parallel with a standard phone handset. 
This means that the AC-701 and a standard telephone handset are plugged in parallel to the same phone socket. Making a outgoing call: The phone is used to dial out and establish the call , once established the user can manually switch the AC-701 to hold the line up. Receiving an incoming call: The phone will ring to indicate a incoming call, the user can then manually switch the AC-701 to answer the call and hold the line up without having to answer the call on the phone
If you need a true auto-answer telephone hybrid then the Clear-Com TEL-14 unit can be used as a stand alone unit The TEL-14 is a 2 channel telephone hybrid with a 4wire connection to external devices (Intercom matrices , sound desks etc..), it also has auto-nulling and level control trim pots.
The TEL-14 needs to be housed in a interface frame either a IMF-3 (with 11 chassis slots) or a IMF-102 (with 2 chassis slots) The TEL-14 can be connected directly using a straight CAT5 cable to Clear-Com Eclipse Omega / Median / Pico matrices as well the older Matrix Plus 3 matrices
The TEL-14 connects only to a ANALOGUE (FAX) phone line. If working in standalone mode make sure to connect the TX data pair to the RX data pair on the "matrix" RJ45 connector of the TEL-14 unit This setup will answer incoming calls , If the customer wants to dial out , they will need to place a parallel phone next to the TEL-14; make the call on the standard handset and then push the "off hook" button on the TEL-14 to hold the line up