8 Muscle Stimulator Circuit

This circuit produces pulses that can stimulate muscle. The signal generator is the 555 timer IC that produces pulse with 73Hz of frequency (Change the frequency by replacing the values of resistor and capacitor using 555 calculator). Unlike other stimulator, this is a simplified one since it uses less parts and no transformer is needed.

muscle stimulator schematic

Part List:

R1, R2 - 2 kilo ohms 1/4W

R3 - 100 kilo ohms potentiometer

R4 - 120 ohms 1/4W

R5 - 56 ohms 1/4W

R6 - 22 kilo ohms 1/4W

C1 - 3.3uF electrolytic capacitor

C2 - 100nF capacitor

C3 - 22nF capacitor

L - 2mH inductor (maximum)

D1, D2 - 1N4007, 1N4004 or similar diode

LED - 3mm or 5mm low power red LED

Q - TIP31C, TIP41C or even 2N2222 NPN transistor

555 IC - CMOS type 555 timer IC (LMC555)

Electrodes - any conducting pads connected to "out" pin

Part List Pinout: Click to enlarge

2N222 pin

555 IC pins

TIP31,41 pins

Circuit Operation:

3V is step up to higher voltage but a very low current. Potentiometer R3 controls the output voltage. LED intensity indicates the output state, normal light when output is high and totally off when output is low. C3 adds more "sting" effect on the circuit, increasing its value increases its sting. Diode D2 protects the transistor from voltage spikes.

Don'ts:

1. Do not use at a very long period.

2. Do not use near your heart or head.

3. Do not place electrodes in cuts, tongue, mouth, and wet body parts.

4. Do not increase the values of C3 and R6, do not remove R6

5.  Do not use this at all! (My advice)

How to use:

Turn on the circuit and adjust the brightness of the LED to zero by adjusting the potentiometer R3. Place the electrodes (out) in your body at least an inch apart. Adjust the potentiometer slowly until you feel the pulses and stop at a level of "sting" you desire.

Note: Circuit is working but use it at your own risk.