A Device That Gives You Reminders When You Need Them Most

To activate it, just walk by

By Mike Rigsby Posted 06.10.2009 at 6:29 pm 8 Comments

You're late for work. As you hustle out the front door, the furthest thing from your mind is the afternoon's dentist appointment that you'd scheduled last week. You'd have probably forgotten all about it — if you hadn't thought ahead by programming a home-built device to give you a voice reminder as you pass it on your way out.

Give Voice to Your To Do List: Peter Pachoumis

Just record your reminder on the device ("Dentist at 3 o'clock," or "Pick up the kids at baseball practice"), set the timer for when you'll need to hear it — up to a week in advance — and from the set time forward, it will play whenever you walk near the attached motion sensor. Sure beats having to remember everything yourself.

DIY Voice Reminder

PARTS

Part	Part #	Source	Price
PIR Sensor Module	276-033	Radioshack.com	$9.99
Recording Module	276-1323	Radioshack.com	$10.79
NPN transistor	276-2016	Radioshack.com	$0.79
.1 uF cap, 50 V	272-1069	Radioshack.com	$1.49
SPST pushbutton sw red	26623	Jameco.com	$0.66
SPST pushbutton sw blk	26649	Jameco.com	$0.7
Perforated board	276-1395	Radioshack.com	$2.79
Wire wrap socket	37411	Jameco.com	$1.19
LM555 Integrated Cct.	27422	Jameco.com	$0.29
1 farad capacitor	142957	Jameco.com	$4.49
Knob	162481	Jameco.com	$1.49
Pot 500K with switch	263848	Jameco.com	$1.59
4 AAA battery holder	216339	Jameco.com	$1.55
Acrylic butter dish	104461	Clearlyacrylic.com	$7.95
1 K resistor	30BJ250-1.0K	Mouser.com	$0.22
470 K resistor	30bj250-470K	Mouser.com	$0.22
4.7 M resistor	66-RCO7GF475J	Mouser.com	$0.25

STEPS
1. Drill holes in your chosen enclosure, following the drilling template. Glue the speaker [A], microphone [B] and motion sensor [C] to the enclosure. Mount the buttons [D] on the outside.

Sound Circuit: Luis Bruno

2. Build the timer circuit board, which lets you specify a time delay after which the message will be enabled. Calibrate the timer.
3. Connect the timer circuit board to the "play" wire from the record module, the "play" button, the power wires from the battery, and the sensor and record modules.
4. Move the switch on the battery holder [E] to the "on" position. Hold the red button to record a message, and press the black button to hear it. Turn the rotary dial [F] counterclockwise to the "off" position. Turn the dial clockwise to set the time delay, after which any movement in front of the sensor will trigger the message.

A schematic diagram can be downloaded here.

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8 Comments

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meeces04

06/22/09 at 8:28 pm

I might be missing something, but I can't find a circuit diagram that I can use to build this project.
I could guess from the picture, but that probably would not work.
Please tell me if I am overlooking something.
Thanks

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leb

06/23/09 at 9:21 am

I agree - there should be a diagram somewhere and I can't find it either.

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Rob Lake

06/23/09 at 3:36 pm

That's three of us who can't find the circuit. Come on guys where's the circiut or is this a belated April Fool's trick??????????????????

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golfero

06/23/09 at 5:33 pm

make that four. how do u make circuit ?????

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hellonet

06/24/09 at 11:07 am

Please, Popsci, notify me and the preceding commenters when the schematic is available.

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leb

06/24/09 at 12:46 pm

I got a schematic by writing the magazine. It's in PDF format and i have posted it at:

www.geezertek.com/popsci/voicereminderschematic.pdf

It's hand drwan and the first page is blank.

LEB

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meeces04

06/25/09 at 10:05 am

Thank you, the diagram is very helpful

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EricIQ-2

09/24/09 at 8:56 am

Are you serious. You guys can't tell how the circuit works, it's simple you just connect the, with the... oh wait no it's take the resitor, and connect that to the... hmmm. Okay I got it you grab all the parts in your hand and spread them all over the floor, and then think of what you want to remember. That way each time you step on an individual part by accident you will will be reminded of what you need to remember.