The IC 555 stun gun circuit is a basic electrical device that generates a high voltage output suitable for non lethal self defense.
Prior to attempting to construct such a gadget, it is crucial to understand the associated hazards and legal consequences.
Circuit Working:
Parts List:
| Category | Description | Quantity | Wattage |
|---|---|---|---|
| Resistors | 33k, 1k | 1 each | 1/4 watt |
| Capacitors | Ceramic 10nF, 100nF | 1 each | |
| PPC 10nF 400V | 8 | ||
| Semiconductors | IC 555 | 1 | |
| Transistor BD679 | 1 | ||
| Diodes | Diode 1N4007 | 8 | |
| Other Components | Transformer primary resistance 8 ohms (0.5 mm super enameled copper wire) Secondary winding resistance 1000 ohms (0.5 mm super enameled copper wire) | 1 | |
| Push button | 1 |
The 555 IC is used in the circuits astable multivibrator arrangement, this circuits output produces a high voltage pulse that may be used as a stun gun.
Below are the circuits working process:
The 555 timer generates a continuous square wave output when it oscillates in an astable state.
The transformer primary resistance 8 ohms is built using 0.5 mm super enameled copper wire.
The voltage is greatly increased by the transformer typically to several kilovolts.
Diodes are used to rectify high voltage input, the rectified output is smoothed using capacitors.
The 20kV, where two electrodes can be linked for the stun gun effect is where the ultimate output is accessible.
R1 and R2 are initially charged by the capacitor C1,the inbuilt comparator reverses the output state when the voltage across C1 approaches two thirds of the supply voltage.
The output flips again when C1 discharges via R2 until it drops below one third of the supply voltage, a square wave is created as this cycle is repeated.
The transformers primary winding receives the square wave output from the 555 IC.
The output voltage is determined by the turns ratio and is increased by the transformer.
An output of high voltage is produced by the secondary winding resistance is 1000 ohms which is built using 0.5 mm super enameled copper wire, the high voltage AC output is rectified by diodes D1 to D8.
The rectified output is smoothed by capacitors C3 to C10.
At the 20kV position a high voltage output is accessible, it is capable of producing a non lethal electric shock when it is attached to two electrodes.
Caution: Be careful stun guns may be harmful, take caution when handling and keep away from skin contact.
Formulas:
In order to provide the high voltage pulses necessary for the stun effect, we normally desire a high frequency oscillation when designing an astable multivibrator circuit for a stun gun circuit that uses the IC 555 .
Formula for Frequency (f):
Using a 555 IC in an astable multivibrator circuit, the frequency of oscillation (f) is determined by:
f = 1.44 / (R1+2*R2)*C
where,
- The resistors attached to the 555 are R1 and R2.
- The timing capacitor attached to the IC 555 is represented by C.
For optimal effectiveness, a duty cycle of over 50% is used in many stun gun circuits.
The following yields the duty cycle D:
D = R2 / R1+2*R2
These values may be changed to provide the appropriate frequency and duty cycle for producing the necessary high voltage pulses in the stun gun circuit by adjusting R1, R2 and C.
Depending on the particular needs and the properties of the high voltage transformer utilized in the circuit, adjustments can be required.
A technique for producing large voltages from a lesser AC or pulsing DC voltage is the cockcroft walton voltage multiplier, often known as a cockcroft walton CW circuit or ladder.
The IC 555 is frequently used in stun gun circuits to increase the voltage produced by the astable multivibrator to the necessary levels for the electric shock effect.
Formula for the Cockcroft Walton Voltage Multiplier:
In essence, the cockcroft walton circuit consists of a ladder shaped arrangement of capacitors Ca and diodes D.
This formula may be used to approximate the output voltage Vout of a CW multiplier with n stages (or levels):
Vout = n * Vpeak
where,
- The CW multipliers n stages or levels, are its number.
- The input waveforms peak voltage before rectification and multiplication is represented by Vpeak.
Because shock gun circuits use high voltages, even if the cockcroft walton circuit multiplies voltage, it is important to take safety measures.
To avoid risks during operation, make sure the right insulation, component ratings and safety precautions are in place.
How to Build:
To build a Simple Stun Gun Circuit using IC 555 follow the below mentioned steps for connections:
- Gather all the components as shown in diagram
- Connect pin 1 of IC 555 to ground.
- Connect pin 2 of IC 555 to pin 6 of IC 555.
- Connect a capacitor C1 from pin 2 of IC 555 to ground.
- Connect pin 3 to base of transistor T1 through resistor R2.
- Connect pin 4 of IC 555 to positive supply of 12V.
- Connect pin 5 of IC 555 to ground through capacitor C2.
- Connect pin 6 of IC 555 to pin 3 through resistor R1.
- Connect pin 8 of IC 555 to positive supply of 12V.
- Connect emitter of transistor T1 to ground.
- Connect collector of transistor T1 to 8 ohms primary winding of transformer.
- Connect base of transistor T1 to pin 3 of IC 555.
- Connect 8 diodes ( D1 to D8) and 8 capacitors (C3 to C8) are connected in a cascaded to create a high voltage multiplier circuit.
- Connect a push button to positive supply of 12V.
Safety Notes:
- Make sure all local rules pertaining to stun guns are followed.
- Recall that creating and utilizing stun guns must be done lawfully and ethically.
- If you want to construct one, be sure to observe safety regulations and take all the safety measures.
- Always put safety first and keep away from hazardous use.
Conclusion:
In conclude, the IC 555 stun gun circuit is a simple electrical gadget that produces a high voltage output appropriate for non lethal self defense.
Recall to follow the law and handle stun guns with caution.