I got the idea from damianzuch; he wanted a remote system for playing practical jokes. I thought of IR remotes over radio remotes for size and security reasons, IR remotes have a less chance of being accidently triggered in public.
The first circuits I came up with worked but the receiver miss fired a lot so I tinkered with it and came up with 5 IR receiver circuits that did different things and 3 small IR transmitters you can hide in your hand. And the reason for 5 different circuits is size the first circuit if powered by button batteries can be hidden in a match box the last circuit might need a tool box with batteries.
Step 1: IR Transmitters
There is a little variation in IR LEDs some run on 3 volts some run on 6 volts with a resistor so you may need to tinker to get the transmitter just right.
Step 2: Transmitter & Receiver Parts & Tools
1. Small push button switch.
2. 3 volt button batteries.
1. Battery 9 or 12 volts.
1. 1N4001 diode.
1. LM78L05 voltage regulator.
1. IR sensor.
1. DM74LS14N Schmitt trigger hex inverter.
1. SN74LS73A JK flip flop.
1. 2N3904 NPN transistor.
1. BT137 Triac.
1. PC817 Optocoupler.
1. Colored LED.
2. 220 uF 16 volt electrolytic capacitor.
1. 100 uF 10 volt electrolytic capacitor.
1. 1 uF 10 volt electrolytic capacitor.
1. 0.1uF ceramic capacitor.
2. 330Ω ¼ watt resistor
1. 1kΩ ¼ watt resistor
1. Bread board or proto board
Step 3: The First IR Receiver Circuit
In the power supply the 78L05 IC regulates the voltage to 5 volts for the IR sensor and ICs.
The IR sensor picks up the signal from the transmitter and sends it to the one shot.
The one shot receives an irregular signal and converts it to a clean square wave output, this one shot is a favorite of mine, it is very simple the larger the capacitor the longer the output signal, this one is 0.5 seconds.
The load on the output of the ICs is low only 5 to 15 ma.
Step 4: The Second Circuit
Step 5: The Third Circuit
Step 6: The Fourth & Fifth Circuits
And now you are ready to make your friends and family into believers.