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