Simple Mixer 4 Input

Here the simple mixer circuit with 4 inputs and 2 operational amplifier (op-amp) modules: A basic mixer suitable for mixing microphones or even effects outputs. The overall gain from input to output is one if the pot related towards the input is full up. You can make this a net gain of ten (or any… Read More »

A/B Box Switch 2 Inputs 1 Output with Dual Op-Amps

This is a A/B Box switch pedal schematic with two inputs and one output and featured with dual operational amplifier modules. This circuit was designed by Rick Barker. This A/B Box effect was originally designed for switching between different harmonica mics. This A/B Box featured low noise dual preamp for better performance.

Very Simple Radio Control (R/C)

Above diagram is a very easy and efficient receiver for actuating garage doors, starter motors, alarms, warning systems and many some other possibilities. The SCR, which has a extremely low trigger current of 30 uA is typical — it demands an input electricity of just 30 uW to activate the relay. A high Q tuned… Read More »

Distortion Booster

The following circuit is an distortion booster effect for your electric guitar. I don’t know whether this circuit is really works or not, you may try this circuit with your own risk. The circuit is very simple with required only ten electronic components : two transistors, two diodes, five resistors and two capacitors. Supply voltage… Read More »

NAND Gate Clock Generator

The following scheme is the clock generator circuit diagram which build based on NAND Gate logic IC. You may use IC 7400 or 4011 for this circuit. The 7400 is a Transistor-Transistor Logic (TTL) type, while 4011 is Complementary metal–oxide–semiconductor (CMOS) type. IC 4011 is cheaper than 7400 but the 7400 is faster than 4011.… Read More »

6A / 0-28V Variable Power Supply

The following diagram is the schematic diagram of variable power supply which will deliver 0 to 28V output voltage at 6A or 8A electric current. Components List: R1 = 2K2 Ohm 2,5 Watt R2 = 240 Ohm R3,R4 = 0.1 Ohm 10 Watt R7 = 6K8 Ohm R8 = 10K Ohm R9 = 47 Ohm… Read More »

6V Gel Cell Battery Charger

The following scheme diagram is the battery charger circuit for 6V Gel Cell battery type only. Components List: R1 = 22 ohm, 1W R2 = 270 ohm R3 = 220 ohm *R4 = 715 ohm, 1% *R5 = 3.57K, 1% *R6 = 1.40K, 1% *R7 = 1.47K, 1% C1 = 0.1uF, ceramic C2 = 0.1uF,… Read More »

FM Receiver Antenna Amplifier

This is the active FM receiver antenna amplifier, used to boost the FM signal catch by the antenna, you may call circuit “FM antenna booster”. By working with only a small handfull of parts you can assembled this kind of reliable FM amplifier circuit. It runs with only 1 UHF/VHF type transistor, MFE201. This amplifier… Read More »

Simple Electronic Combination Lock

The following diagram is a very easy and simple electronic combination lock based on IC LS7220. Component Part List: C1 = 1uF 25V C2 = 220uF 25V R1 = 2.2K Ohm Q1 = 2N3904 / 2N2222 D1 = 1N4148 / 1N4001-1N4007 K1 = 12V SPDT Relay / Any appropriate relay with 12V coil U1 =… Read More »