Saturday, January 26, 2008

The Diabolical Phone Switch

Sick of teenagers abusing the use of your house phone? Well your prayers for a solution have been answered. I give to you the Diabolical Phone Switch. Original article available here.

 The Disclaimer
First let me say that I will not be held responsible for any of the dumb crap that may result from any ideas you may derive from the following text.

I am basically presenting a device that I created in a few nights worth of free time to cure a pesky problem I have been having with phone abuse from three teenage daughters.

Be aware that this device uses line voltages from an AC power outlet, and that proper care should be taken whenever line voltages are to be worked with. So be safe and don't be stupid!

But Why?
I like to think of myself as a reasonable person. I fully understand that teenagers like to use the phone, text message, and generally wallow in their own ultra-dramatic pubescence. Teenage girls are the worst for this. And having three of them REALLY makes things difficult when they all wish to use the house phone at once.

Despite the fact that there are 24 hours in a day, this still does not seem to be enough for teenagers who wish to blabber all day and night.

Because of this, I find myself threatening to disconnect the phone at a predetermined time of the evening just so I can get some sleep. Furthermore before my nightly slumber I have to either walk around and collect all the phones or unplug the main line.

This is no joke they will literally stay up all night on a school night talking non-sense.

To remedy this and save some sanity I decided that some automation might take care of this problem. This way I don't have to lift a finger to insure that the phone goes off at a certain time of night. 

What I need it to do
Basically I need a machine that I can put into the main phone line, which will turn off the phone as per a schedule that I can control. I will also need it to default itself to enable the phone line if power is lost in case of emergency.

To accomplish this I will use a lamp/Christmas light timer that has the ability to be programmed on a weekly basis.

When triggered the timer will enable a 12-volt wall wart (Transformer), enabling a relay, which is normally closed. This breaks the contact in the line disabling the phone. The timer will also remove power to the transformer to release the relay and re-enable the phone.

The Pieces and Parts of it all
Okay, so this is where you need to put on your thinking cap.

Going through the parts required you want to make sure that you choose a timer that will suit your needs. I had one laying about that allowed me to program a weeks worth of scheduling.

As for the wall transformer and relay. You want to make sure to match the voltage of the transformer to something the relay can handle. The smaller the voltage and current consumption of the relay the better. Also the relay will need to be able to switch at least two wires. Each phone line is a pair of wires. Finally you'll need a pair of phone jacks and a box to mount everything in. 
Start soldering it all together
Be careful and double check everything that you are soldering together. Here you can see the relay being soldered.

Also I needed another wall transformer since the other one didn't produce the correct voltage/current that was needed for the relay.

In the back you can see the phone jacks. We will be utilizing the red and green wires on both the jacks. When wiring to the relay make sure that green connects to green and red connects to red.
Getting it together and testing
 Here we see everything soldered together, and ready to be tested. The timer that I have allows you to trigger it manually. I used a multi-meter set to check for continuity to insure the relay was working properly.

Once everything checked out, it was time to mount into a box.

 Scary isn't it?
Looks more like a time bomb then a device to cut off a phone-line doesn't it? It's packed into the box a little tight but I had to use what was on-hand. I kept the components secured to the box using Velcro on the bottom of it and then put Velcro on each component. It's not fancy but it seems to work.
I also cut a few holes in the lid for the phone jacks and the A/C line cord. Once the timer is programmed I tape the lid on, plug in the phones and wait for the cry's of pubescent angst. My days of yelling to get off the phone at a reasonable time are FINALLY over.