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Coin Cell Challenge Entries

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97 projects
7.4k
22
33
A clone of National Semiconductor's LM3909 IC using discrete components on a PCB.
Project Owner Contributor

Disintegrated LM3909 - 1.5V LED Flasher

dillon-nicholsDillon Nichols

4.5k
13
28
An Arduino powered birthday reminder device that'll wish you happy birthday for 50 years on a single CR2450 coin cell.
Project Owner Contributor

Birthday Alarm That'll Run for 50 Years!

vishnu-mohananVishnu Mohanan

52.9k
190
114
This project using an ESP8266 to find the password of a WiFi access-point with PBC enabled.
Project Owner Contributor

WiFi cracker ESP8266(PBC)

sagar-naikSagar Naik

6.7k
75
76
whowhow. whowhow. - formally known as purple rider
Project Owner Contributor

K.I.T.T. - KNIGHT RIDER badge/brooch

davedarkodavedarko

4.5k
22
22
In this project I will make an indoor gardening system to take care of my sweet plant and its beautiful flowers
Project Owner Contributor

Arduino Indoor Garden

diy-guy-chrisDIY GUY Chris

905
8
7
Lorentz dreams about metal horses
Project Owner Contributor

pic-o-matic

robert-matejaRobert Mateja

213
4
4
Coin Battery Powered Open Fridge Alarm.
Project Owner Contributor

Open Fridge Alarm

mariusznowakengmariusz_nowak_eng

719
4
2
A small circuit inside an enclosure, both optimized to resist a hit to the ground
Project Owner Contributor

Airsoft sonic grenade

eduardEduard

31.5k
92
116
If you like happy, easy to build projects, this is not for you. This project is only for people who like to be miserable and frustrated.
Project Owner Contributor

An Unfortunate SMD Project

makersboxMakersBox

335
4
4
I'll be sharing with you my experience of how i started from a simple idea to a finished product
Project Owner Contributor

VibClock

foxmjayFoxmjay

201
1
1
Really simple light-up pop up card, using 2 LEDs, copper tape and a CR2032 coincell battery.
Project Owner Contributor

Quick LED Birthday Card

amandarAmandar

1.6k
6
7
This is a 3d printed mini led lamp ran on a 3v coin battery.
Project Owner Contributor

3v coin powered Articulated Mini Lamp

odddavisOddDavis

71.3k
337
293
Multi-year always-on LED replacements for gaseous tritium light sources
Project Owner Contributor

TritiLED

ted-yapoTed Yapo

925
754
7
The first digital watches had this red bubble display, you need to push a button to see the time.
Project Owner Contributor

Retro Wristwatch

saarbastlersaarbastler

7.3k
28
38
A persistence of vision (POV) display with five 0805 LEDs piggy back on an ATTiny13.
Project Owner Contributor

Tiny POV

jens-haukeJens Hauke

2.2k
22
31
Small sized 555 timer based piano.
Project Owner Contributor

555 piano

alexander-ryzhkovAlexander Ryzhkov

13.8k
130
121
badgy is a rechargeable coin cell powered ePaper display with WiFi connectivity
Project Owner Contributor

badgy

w4ilunw4ilun

472
6
12
Here I have a Maker Gummi Bear that can be worn as an electronic badge. It contains LEDs and is powered by a single coin cell battery.
Project Owner Contributor

Maker Gummi Bear

rachelRachel

10k
100
85
A little UHF transmitter can be located with a directional antenna.
Project Owner Contributor

Tiny Low-Tech tracking transmitter

tomTom

11k
33
38
A pranking device to annoy your friends... or perhaps an entire college campus.
Project Owner Contributor

ATTiny Low Power Prank

joseph-primmerJoseph Primmer

17.9k
10.6k
70
A smart sensor Node to trigger an action on a smartphone each time a physical change is detected (temperature, displacement, click...)
Project Owner Contributor

Triggy - Sensor Node for Life Automation

vinchVinch

14.5k
25
15
This project describes the use of a coin cell for powering the Esp8266 by building a remote control for Phillips Hue Lights
Project Owner Contributor

Solved: Esp8266 powered by coin cell

gelstronicGelstronic

661
5
7
Coin cell powered 555 timer with ultraviolet LED coated with glow in the dark paint to mimic a firefly.
Project Owner Contributor

Fireflies

jux-crowJux Crow

128.7k
1.3k
677
A family of tiny robots, each with their own way of life.
Project Owner Contributor

Tiny robot family

shlonkinshlonkin

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