The adapter then goes on {TAIL ~ hook} , terminating {HEAD ~ the call} to the PBX 
The adapter then goes on { TAIL ~ hook } , terminating { HEAD ~ the call } to the PBX
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH