Home Hacking Projects for Geeks

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Chapter 11, Keyless Entry Welcome Home

in there is difficult to describe, but

one thing worth mentioning is that

you can’t drive your relay and the

LED on the outer lock at the same

time, so there’s no need to connect

the wire back to the harness leading

to the outside bezel. This frees the

inside harness to have its connec-

tor cut off and its wires pulled back

through the lock’s circuit board to

the battery side.

You may want to keep the connec-

tor on the LED harness to make it

easier to change the batteries. If

so, you’ll have to carefully remove

it to enable you to pull the harness

through the board to the other side.

You can accomplish this by using a

hobby knife to press down the tiny

ears that retain the contacts in the

connector.

The Control Medium

Although there’s nothing in the con-

trol medium component that you’ll

actually be building or modifying,

it’s still important to discuss here,

especially if you aren’t planning

to implement the full system. The

hardware that makes up the control

medium can be implemented par-

tially if you intend to omit the dis-

patcher for the sake of simplicity.

The control medium enables the

transmission of control information

to various endpoints, such as a lamp

or your computer. It consists of an

RR501 plug-in RF base, your home’s

power lines, and an optional CM1