My neighbor asked me to check out and possibly repair his doorbell. He has a Panasonic D816 switch upstairs which is intact and the downstairs doorbell is supposed to ring his phone. Then he dials 5 and engages the electric strike to open the door. I think he said he can dial a different number and open the garage door. The doorbell assembly itself (downstairs) has totally disintegrated from the moisture at the ocean. The speaker crumbled in my fingers, the button wires were gone, etc. There was a unit connected to it that seemed to be the interface for the power and electric strike. I have a 3-pair CAT3 going up to the switch and two power pairs available for a totally new solution. Any suggestions from the Panasonic experts? I think even a caveman like me could repair this thing since the wires are all in place. The power pairs go all the way back upstairs to an outlet near the switch. He has the door module on the D816 installed already obviously. Ideally, someone would ring his bell, he could converse, and press a button for the door(s) release.