Here the 35W power audio amplifier circuit based on LM391. Inductor L1 is constituted by 20 coils of wire, with thickness 0.9mm, round resistor R16. The transistors Q3-4 are the final amplification section, it should be placed on heatsink. If are used the Q3-4 in packing TIPxxxx they can be placed straight above in PCB.… Read More »
This is the circuit diagram of car audio system anti theft security which can be effectively used to protect and secure your expensive car audio system from stealing. This simple circuit designed based on popular CMOS NAND chip CD4093,. When the circuit is switched on via switch S1, the indicator LED1 will glow and the… Read More »
Here the SW transmitter circuit based on IC BEL1895. This particular transmitter circuit works in shortwave HF band (6 MHz to 15 MHz), and can be applied for shortrange communication and for educational purposes. The circuit is composed of a mic amplifier circuit, a variable frequency oscillator, and modulation amplifier stages. Transistor T1 (BF195) is… Read More »
This is the circuit diagram of laser communication system that transmit the sound or music signals by way of a laser beam. The intensity of the laser beam varies together with the amplitude of the sound signal. The variation within the intensity of the laser beam is converted into a variation in the voltage level… Read More »
The following diagram is the schematic diagram fo Car Horn, you may try this circuit for your car modification… 🙂 Components List: R1 = 68K R2 = 2K2 R3 = 56K R4 = 3K3 R5,R6 = 4K7 R7 = 10K Pot/trimpot C1,C2 = 22nF C3,C5 = 100nF C4 = 1nF C6 = 220uF/25V IC1,IC2 =… Read More »
Here is the USB sound card circuit based on PCM2706 which dedicated for USB audio. With USB controller module inside PCM2706, there is no more additional programming to the IC. The computer system will automatically detect this circuit when connected to the USB port. You will get stereo audio channel output from this circuit. Schematic… Read More »
This circuit is a wireless car alarm system that is built using two circuit modules, namely modules of transmitter and receiver modules. This circuit works on FM radio waves. Car alarms can be used on vehicles that have a 6-12VDC power supply. You can use the voltage stabilizer if your car power supply is too… Read More »
The following is 4 x 25W quad audio amplifier circuit (amplifier with four inputs and four outputs) based TDA7381. This amplifier is designed for car audio system, but you can also use this circuit for other purposes. This circuit has a design very simple and very easy to build. Schematic diagram: If properly layouted and… Read More »
This is the circuit diagram of 2 x 22W stereo car audio amplifier. The circuit is powered by a single IC TDA1553 with some external components, this IC will handle your stereo car audio system. The TDA1553CQ is a monolithic integrated class-B output amplifier in a 13-lead plastic DIL-bent-SIL power package. It contains 2×22 W… Read More »