The Diabolical Phone Switch




About: I like to tinker and I like to learn, and if one can support the other then thats great.

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.

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Step 1: Disclaimer

First let me say that I will not be help 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 teenaged 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 tinkered with.

So be safe and don't be stupid.

Step 2: 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 pubescence and ultra-drama. Teenaged 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.

Step 3: What I Need It to Do

Basically I need a machine that I can put into the main phoneline, 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), which will trip a relay, which is normally closed, to break the contact in the phone line disabling the phone.

The timer will also remove power to the transformer to release the relay and re-enable the phone.

Step 4: The Pieces and Parts of It All

Ok so this is where you need to put on your thinking cap.

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

As for the wall transformer and relay. Be 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.

Step 5: 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.

Step 6: 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.

Step 7: Scary Isn't It?

Looks more like a time bomb then a device to cut off a phoneline doesn't it? It's packed into the box a little tight but I had to use what was onhand.

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 crys of pubescent angst.

My days of yelling to get off the phone at a reasonable time are over.

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    127 Discussions


    4 years ago

    Bravo! Puts the owner (and the one who pays the bills) in complete control. Excellent idea!


    5 years ago on Introduction

    my only concern with this would be emergency number access. but hay
    it would be pretty simple to set up 1 or 2 phones downstairs or in a
    public area that has direct access and all other lines switched. you
    know when the hallway lights on, somebody's using the phone when they
    shouldn't be.

    albeit 15 times more cruel, I would do the same
    approach with one of those RF remote Christmas light switches. ( just
    for the enjoyment of watching somebody on the phone and to have it
    suddenly go dead, and then they hang up and it suddenly works again!)

    better yet get a phone with a line in use light, And put it by your bed
    and wait for a unsuspecting stranger to listen to their call and
    comment back.

    but wait, doesn't everybody now have cell phones and use text messaging.

    also i was curious what type of relay you used and if you get interference or noise on the line. I have been pondering something similar to switch between fax machine and dial-in modem via remote web control.


    11 years ago on Introduction

    I'm 16 and I hate phones. (no, seriously I won't answer the phone unless no one else is home). I hate people that talk on cellphones and totally ignore what is going on around them.

    17 replies

    Reply 11 years ago on Introduction

    I'm 14 and I hate talking on the phone as well. I seriously never use my cellphone for anything other than occasionally texting.


    Reply 10 years ago on Introduction

    I must ask....if there are *scrolls up to count* [a minimum of] four "one of a kind teenagers" then aren't they in fact four of a kind? and did you say anything other than that on this Instructable? :D


    Reply 11 years ago on Introduction

    Here's one for ya'. I'm 15, don't own a cellphone and don't want to, I only use the land line when I'm on the internet (dial-up), and (going off topic) I have vinyl records and 8-track tapes. Also, what does"BTW" mean?

    John SmithLinuxH4x0r

    Reply 11 years ago on Introduction

    14 in 4 days, and I HATE, and I mean HATE, answering the phone...can't stand it. nice instructable, btw.

    John SmithAhmedqatar

    Reply 11 years ago on Introduction

    Haha, I use AIM for talking to my friends. And no, I don't talk like, "hey dude r u gona be at skool tomaroww? kool" I talk there just like I do here...ha

    John SmithLinuxH4x0r

    Reply 11 years ago on Introduction

    Ha, I don't know what I meant...actually, haha I was TRYING to say that I type correctly without most of the IM slang most people use on IM's. : )

    LinuxH4x0rJohn Smith

    Reply 11 years ago on Introduction

    I know what you mean. I'm not a grammar nazi, but I hate people who spell like that. I'm personally not a fan of aim, but sometimes on gmail's chat thing I will use u, r, k, and stuff like that.

    John SmithLinuxH4x0r

    Reply 11 years ago on Introduction

    Eh, I like me AIM. Course I haven't had anything else....ha The only slang stuff I use is the occasional WTF.