This is a simple how-to guide on making  a cheap remote/wireless ignition for a spud gun or other application. It uses a doorbell circuit to transmit an RF signal to activate a relay that completes a 9V stun gun circuit, turning it on. Can be made for less than $20.

Components (you don't have to use the exact model part as I have, any with the same specs will do):
1x Arlec 149 door chime (any wireless door chime will do)
1x 100uF 10V capacitor (10ML100MEFC6.3X5)
1x 1A 200V standard diode (1N4003)
2x SPDT on/off toggle switch
1x key on/off switch
1x momentary button
1x project box
1x 3V DPDT relay (IM01TS)
1x 100kV stungun

Wire stripper
Soldering iron
Box of jewellers screwdrivers (not required but helps when fiddling with small parts)
Insulation tape
Heat shrink (not required but is recommended)

Credit for the two circuitry diagrams and alternative relay wiring graphic, Spudfiles member: dewey-1

Step 1: Modifying the Door Chime

My particular door chime receiver was powered using two AA batteries in series, providing 3 volts. I used a voltmeter to measure the output when the door chime was activated and it too was 3V. If you don't have a voltmeter, don't worry as your output will probably match the circuitry voltage.

Determine the voltage applied to the circuitry of your door chime receiver, some are 3V some may be higher like 5V. Doesn't matter which voltage it is, any will do.

First, you need to cut the two wires that are going to the speaker. Once that is done, determine which wire is positive and which is negative by connecting them to an LED, voltmeter or other electrical component that can tell you the polarity. Another way is by finding the transistor near one of the wire terminals, it seems that the transistor is generally connected to the negative wire.

Next, we need to determine which relay we need. The relay is an electrically operated switch, when a low powered signal is sent to a relay, it closes a switch and allows the signal to carry on to the rest of the circuit. In this case, the relay will be completing the circuit of a stungun. When you attach a 9V to your stungun circuit, it should spark continuously but if we put a relay between the 9V positive terminal and the stungun positive terminal, the stungun can't spark until the relay has been activated.

If your door chime circuit is also 3V, find a 3V relay similar to the one I used (model number is on the components list).
See what happens if you put a &quot;diode pump&quot; on your relay driver - you might find it triggers more reliably/ pulls in quicker. Basically, it would act as a rectifier for the AC tone.<br><br>Steve
thanks for the suggestion, I shall do some research and testing
Very neat 'ible by the way. <br><br>Have you tried to find where the tone IS generated on the receiver ? I'm pretty sure the receiver will generate a &quot;digital&quot; signal which turns on the tone - poke around with an oscilloscope, if you can find one, and take a look. <br><br>Steve

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Bio: I love building things that shoot other things whether they be small plastic BBs or 135g steel ball bearings. If you need help with a ... More »
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