Here the simple, low cost and easy audio booster circuit. It uses a transistor of 2N3392 ad the main amplifier. Component List: R1 = 47K R2 = 470K R3 = 10K R4 = 560R R5 = 270R C1 = 0.1uF/25v C2 = 3.3uF/25v C3 = 470uF/25V P1 = 100K Q1 = 2N3392 D1 = 5mm.… Read More »
The following image is the scheme diagram of six LED stereo VU display circuit which build using Dot/Bar Display Driver IC LM3915. This VU display should be connected before amplifier module circuit. You may connect this circuit at pre-amp output, tone control input/output or equaliser input/output. This circuit powered with 12V DC supply. About LM3915:… Read More »
The following diagram is the circuit diagram of 20 band stereo graphic equaliser which will controlling the audio signal in specific frequency range. The power supply used for this circuit is symmetrical (dual polarity) type, 15V DC.
This a two station intercom. It uses two wires to run between each intercom unit. Each is self contained with its own battery, speaker, microphone and amplifier circuit. An LM386 audio power amplifier is used. It is widely available, used a minimum of external parts and is well suited to battery operation. It will give… Read More »
This is the circuit of LED color fade effect. Just like the name of the circuit, the light intensity of LEDs in this circuit will fade from high intensity to low intensity and then off. Here the final result preview:
This is a mini fm transmitter circuit. I think this is the simplest one. Simple, easy and of course… inexpensive… The supply voltage is between 1.1 – 3 Volts with power consumption is 1.8 mA at 1.5 Volts. This circuit should be able to cover 30 – 50 meters of range max. at 1.5 Volts.… Read More »