From a Coffeemaker to a Travel Alarm Clock




About: I am a photographer, a tinker, an electronics technology engineer, and author; I write short stories and poetry for the love of writing. I started writing poetry in high school over thirty years ago where I ...

I am a big believer in a greener way of life so I reduce reuse recycle and repurpose, to this end I gather many things put out for the garbage, the computers I get my wife likes to rebuild and gives them away to people that can’t afford a computer. The other things I get to repair repurpose or strip for parts.

In this Instructable I am going to repurpose a coffeemaker into a travel alarm clock, when I worked as a truck driver I had this travel alarm clock I bought in a truck stop for $20.oo. It was advertised not to use near a graveyard or it would wake the dead. I went through three of these alarm clocks they had the knack of growing legs and walking off.

I found the coffeemaker while I was helping my friend George make his deliveries, at first I wanted to use the clock circuit for testing LCD displays. Later that week I was visiting my brother and he mentioned he didn’t have an alarm clock and I got a new purpose for the clock circuit.

All the parts I used in this Instructable were salvaged but the battery I bought at the local dollar store making the total cost of construction one day and one dollar.

Step 1: The Coffeemaker

The coffeemaker was a Kenmore ADC coffeemaker; I plugged it in to make sure the clock worked.

Now that I knew the coffeemaker was working I dissembled the coffeemaker from the bottom up by removing all the screws from the base and then the components inside.

There are a few deep screws so you will need a long 12 inch Philips screwdriver.

I keep all the working parts that I may have a use for later.

Step 2: The Clock

There were two circuits in the coffeemaker the clock and control circuit and the power and switching circuit.

There were 4 wires going between the two circuits and a thermal control line to turn off the burner when it was at temperature.

I removed the thermal control wire and tested the clock making sure the running LED light lit up and the relay tripped.

Step 3: Testing

With my multimeter I found out what each wire did and checked the voltage and the current of all the functions of the clock paying close attention to the current when the relay to the heater was tripped.

The voltage to the clock was higher than the 5 volts marked on the circuit board this was probably due to the power circuit not having a regulator and the current went up when the relay was tripped.

Step 4: The Alarm

From my salvaged parts I selected a Piezo buzzer with a built in driver circuit and replaced the heater relay. I tested the clock circuit once more making sure the current did not vary much from the original circuit setup.

As with the heater relay the current doubled.

Step 5: Upping the Buzzer

The buzzer was loud and annoying but I wanted to see if I could make it louder with a larger Piezo buzzer so I built a driver circuit for a Piezo buzzer I salvaged from an out dated smoke detector. We all know how annoying a smoke detector can be if you have ever set one off.

There was no appreciable difference so I decided to go with the buzzer with the built in driver circuit.

Step 6: The Finished Wiring

There were four wires to the clock circuit one power supply wire, one common, one relay that I used for the buzzer, and one for a function I did not need.

I removed the wire for the function I didn’t need.

The relay wire was a ground switch so I connected the Piezo buzzer circuit to the power supply post and the relay wire.

Next I connected the battery terminal to the clock power supply post and the common post.

Once I had all the connections made I tested the all the functions of the clock making sure it went off at the time I set it to go off.

Step 7: The Finish Assembly

Everything working it is time to the face back on the clock and attach the buzzer and battery.

First I glue the lens cover on the LED

Then I screw the clear face on the clock with the labeled control buttons.

And using two sided tape I attach the buzzer and the battery to the back of the clock in a manner that uses the battery as part of the support to hold the clock upright.

Last I test all the functions making sure the clock goes off at the time I set it for.

Step 8: Your New Alarm Clock

There you have it a coffeemaker repurposed as an alarm clock and remember, “DO NOT USE NEAR A GRAVEYARD IT WILL WAKE THE DEAD.”



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    18 Discussions


    3 years ago

    I have a clock that I pulled from a coffeemaker that had a burned up heating element. I'd like to make an alarm clock from it on AC power and attach a small strobe light to the alarm. (I'm hard of hearing and alarms loud enough for me can bother next door apartment neighbors.) Maybe a relay would be the best option, if I can find something with a repeat function that would make it flash at a safe rate. I wonder if anyone knows what a safe rate is, or where I can find this info?

    1 reply
    Josehf MurchisonThereseS1

    Reply 3 years ago

    An SCR might be better for turning on a strobe than a relay, but yea flashing speed has been known to induce seizures in people.

    A vibrator might be more effective, you would be surprised at how effective a small movement can wake you.


    5 years ago on Step 8

    Inspiring, thanks! Any reason the relay couldn't turn on an AC radio? My clock radios dieing, and I have radios stashed away.

    1 reply
    Josehf MurchisonSparkyOR

    Reply 5 years ago on Step 8

    Should be no problem the buzzer went to +V and the switch was on the negative of the buzzer so a PNP transistor or a SCR should be able to turn the power on for a radio.



    5 years ago

    I like that idea! I have three disassembled coffee maker s right now with no plans for them so I just might try this.

    1 reply

    I used a Piezo buzzer with a built in buzzer and compared it to a feedback Piezo buzzer I built the driver for so yes you can use a Piezo buzzer.

    There is a down side the9 volt battery only works for a week so I upped the battery to a 6 volt aa battery pack for a longer life. Right now I am finding out how long it lasts.


    5 years ago on Introduction

    I've done similar with a couple of old Mr. Coffee models (the old LED style).. Yes, it's easy to convert the timers.. What irks me, is how much people just simply toss the maker, not even checking to see if the thermal fuse is the only thing blown.. But, their loss, my gain. :-) My version, I used to take a plastic box, and mount the clock through a cut rectangle, then mount a simple 2-prong AC outlet, then either a radio or a simple AC buzzer pulled from an old washing machine..

    1 reply

    I’ve been thinking about adding an AC power supply and a rechargeable battery to the clock, the 9 volt battery only lasts a week.

    It is very accurate and easy to use for that week though.



    5 years ago on Introduction

    very cool. ... I noticed you said you were a long-haul truck driver.... I was wondering if it'd be a cool idea to put a couple of resistors in line on one of those plugs that goes in the lighter socket in the truck. drop the 12 volts to 9 like the lil' battery puts out. then you could switch off as needed between the 9 volt battery and the lighter socket.

    1 reply

    You could do a more reliable job with a LM78L09 voltage regulator since it runs on less than 20 ma, but yea it can be done.


    5 years ago

    Great job! But, the way travel is now, you couldn't go on flights with that, looks like a bomb timer or something peculiar.

    1 reply

    5 years ago on Step 8

    Very nice work :) lol i wish my alarm woke the dead...mine wakes *nobody!*

    1 reply