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Gadget Freak Case 110: A Fridge That's Alert for Midnight Snacks

By Design News Staff -- Design News, October 22, 2007

When you've popped in your fridge alarm, getting peckish in the middle of the night and forgetting to close the door — along with escalating electricity bills — will be a thing of the past. Italian inventor Flavio Dellepiane has designed a 3V battery-powered fridge alarm that beeps if you leave the door open for more than 20 seconds. When the fridge lamp illuminates, the alarm's photo resistor lowers its resistance, the IC starts counting down and, after a preset delay, the piezoelectric buzzer beeps for 20 seconds.

Build Instructions | View Parts List | Post a Comment

Amt	Part Description
2	PCB Mount holders for 1xN cell	839-3078
1	10k 0.33W Carbon Film Resistor	296-6300
1	Photo Resistor (ldr)	699-0002
1	100k 0.33W Carbon Film Resistor	296-4743
1	10 nF 100V Polyester Capacitor	995-0018
1	100 uF 10V Electrolytic Capacitor	859-0122
1	1N4148 75V 150 mA Diodes	935-0242
1	74HC4060 14-bit Binary Counter & Oscillator IC	236-1836
1	BC337 45V 800 mA NPN Transistor	431-0466
1	Piezoelectric buzzer, 13.7 mm	623-1957
1	1.5V N Alkaline battery	884-5175
1	Black ABS potting box with lid, 64 x 43 x 25 mm	806-6955
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Talkback

So, what''''s new here? When I was 12 years old, some 65 years ago, I did essentially the same...
- 2007-11-19 13:28:22
The opening paragraph has a typo. It should read: "plasma globe", NOT: plaza globe.
- 2007-11-05 09:34:04
Could a more powerful device of this design possibly be used to detonate road side Improvised...
- 2007-11-05 09:08:03

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