This is the electronic circuit diagram of aquarium temperature probe capable to monitor the temperature of water and indicate the rise in temperature through audio-visual indicators. This circuit uses diode 1N34 as the temperature sensing probe. The resistance of the diode will be vary depends on the temperature in its vicinity.
This is the schematic diagram of Infrared (IR) cordless headphone. Maybe it also can be called “wireless headphone”, but it use infrared as sound signal carrier. It use a pair of circuit diagrams that are IR transmitter and IR reveiver. Using this low-cost project one can reproduce audio from TV or other electronic devices without… 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 »
Here the short wave AM Transmitter circuit design diagram. The circuit is quite simple and easy to build since it applies only a few electronic components. The primary feature of this transmitter is that it really is absolutely free from the LC (inductor, capacitor) tuned circuit and runs using a fixed frequency of 12 MHz… 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 »
This is the circuit diagram of stereo tube amplifier using 6SQ7-GT and 6V6-GT. The tube amplifier circuit is uses the total of 5 power vacuum tube. The diagram is based on the output section design of typical late 1940’s old AM Trutone radio with 6 tubes. The output will be 4 Watts per channel (2x4W… Read More »
This is the schematic diagram of sound activated light or lamp. The lamp or light will be turned on while a loudy sound catch by the microphone (for example: hand clap) How this sound activated light works: The condenser microphone fitted inside a position to catch the sound and generates AC signals, which pass by… Read More »
This is a simple 20W bridge amplifier based on TDA7240A. This circuit is designed for car audio system, but you may use this circuit for your small home audio application… 🙂 . Schematic Diagram: This circuit operated with 18VDC asymmetrical power supply (positive (+) and ground only). Mount the power IC on a heatsink to… Read More »
Here is the circuit diagram of 4 x 35W quad bridge amplifier. This is a power amplifier that has four input channels and four output channels or commonly called the quad amplifier. Power amplifier is designed specifically for car audio system applications. With a fairly large output power per channel, low distortion and low output… Read More »