{TAIL ~ a coupling device} which removably couples the portable measurement device to a port in the moveable barrier operator, the measuring circuit generating {HEAD ~ an impact force signal} representing an impact force measurement and effecting transmission of the impact force signal from the interface to the movable barrier operator 
{ TAIL ~ a coupling device } which removably couples the portable measurement device to a port in the moveable barrier operator , the measuring circuit generating { HEAD ~ an impact force signal } representing an impact force measurement and effecting transmission of the impact force signal from the interface to the movable barrier operator
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH