Handmade bomb with TNT and countdown timer
date: 16.06.2010

How to make a bomb like in movies?

бомба с таймером

Just a toy but good looking and with countdown timer and working wires.

This is bomb with 7-segment LED indicators was made for one military game.
6 TNTs made from wooden stick - wrapped with gray paper and marked "explosive" by thermotransfer tehnology to look like an old one.
Inside TNT goes wire to timer. Second wire connected by "banana" connector. Looks like detonator and makes it reusable - do not need to cut wire to disarm a bomb.

самодельная динамитная шашка

сборка бомбы

Two type of wires - first for disarming, second for explosion. All disarming wires connected into chain an connected to "disarm" pin on the timer. All explosion wires connected into chain and connected to "explosion" pin on the MCU. Thru this 2 pins microcontroller controls all 9 wires.

If player unplugged wrong wire, timer stops and and shows "OOPS" on the indicator. If unplugged "disarm" wire, indicator shows 4-digit "bonus code".

Reset pin connected to garage door controller and can be set to start value distantly.

Reserve reset button hided in timer and can be pushed thru small hole in the body.

Example schematic
бомба - схема управления семисегментными индикаторами

Плата управления семисегментными индикаторами на AVR

7-seg LED PCB
Плата семисегментных индикаторов

Indicators used - KW1-561CSA from ebay.
microcontroller - attiny2313A

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