reid@decwrl.dec.com (Brian Reid) (01/28/88)
I'm in the middle of rebuilding my house. Actually, I'm 10 days from being done enough to move back into it. My job is to automate things, so I thought for fun I'd automate some of my house. One of the principles I use when I'm automating stuff at work is to automate as much as I know how, then live with the semiautomatic system for a while to gain experience with it, then re-engineer. Since there are very few home automation systems to use as a prototype, I kind of winged it. Here's what I did. Communications I installed 25-pair telco cable into every room. These cables terminate inside the wall in a standard telco connector. For the moment, I have attached a 6x8 harmonica (6 8-wire modular connectors) to each connector, and mounted the harmonicas in a 3-wide wall plate. Into my computer room I have 3 such cables. I also installed 2 75-ohm coaxial cables to every room. These terminate in ordinary F-connector wall plates. All of these wires come together in a utility room. The 25-pair cables are punched down in standard telco type-66 punch blocks, and crossjumped as needed. The coax is connected to a pair of broadband amplifiers (500 MHz) which each feed into a 16-way splitter. This gives me 2 500-MHz video channels from the utility room to each room of the house, and 25 twisted pairs to the same locations. Also I have a bunch of random cables pulled into this room and punched down, such as doorbell buttons, several thermostats, exterior sensors, etc. All of this is completely standard technology. The twisted pair is pretty much the way that modern commercial buildings are wired for terminals and telephones, and the 75-ohm coax is the way that people run cable TV in apartment houses. I decided not to run Ethernet because with all of that twisted pair, you really don't need Ethernet. Audio I have run 12-gauge speaker cable through the walls into those rooms where I believe I will ever want speakers or audio systems (all "public" rooms, but not bedrooms or bathrooms). These cables terminate in ordinary-looking electrical outlets, except that if you look closely you will see that the prongs of the requisite electrical plug are different, so that a speaker plug cannot fit into an electrical outlet, or vice versa. The particular outlet that I chose is designed for use with 400-Hz 120-volt power, which I am told is sometimes used in avionics. In every mechanical way they are just like an ordinary duplex electrical outlet. The audio wires come together in a bank of connectors placed where I intend to put my audio power amplifier and audio switchers. Power Every room in the house has a separate circuit for wall plugs and for lights. Rooms like the kitchen and computer room, which need special-purpose circuits, have more. All of these circuits come together into a special Square D breaker box that has 84 different circuit breakers in it, many of them GFI's. Heating I have forced-air heat, with a set of electrically-operated dampers that can open and close various of the ducts. These dampers run on 24-volt AC, and (of course) the wires for them go to the wiring central in the utility room. There are zone thermostats in various regions around the house. The thermostats all connect to a controller box that I have built, which considers their various inputs and then decides how to set the dampers in order to route the hot air to those portions of the house that seem to want it. I have heard from a friend that you can buy a telephone-operated thermostat, so that you can phone your house from the airport and tell it to warm up before you get there. As soon as I find where to buy one of those I will add it to the collection. Miscellaneous There is a touch-tone pad on the outside of my house that is connected to the wire room. At the moment it is connected to a decoder box that I have jimmied together that will process a 7-digit password and open an electrically-operated door lock. Such locks are expensive, so I only have one of them, but one is all it takes to get into the house. I have humidity and temperature sensors in the wine cellar, but at the moment nothing more than a strip chart recorder listening to them. I have a few Radio Shack remote-control switches and outlets, and a Radio Shack controller for same. I've dissected the controller so that I can remotely send it signals, and I've punched its access wires into a phone block and crossjumped them to some of the pairs that go to my computer room. I haven't yet bought the interface card that will let me have the computer control those lights, but it will be easy once I buy the card. In various of the communication connectors, I have plugged miscellaneous wires that need to run from one room to another, for example fader and mute circuits for the speakers whose amplifier is in another room. An intercom to the baby's room. Ordinary telephones. I move back into the house in 2 weeks, and I'm sure I'll be adding lots more tricky automated toys once I'm living there again. Brian