Free Simple Circuit Diagram
This touch tone decoder can be used to decode a DTMF (Dual Tone Multiple Frequency) signal from a telephone device or from other generator. Using the frequency values shown in the schematic diagram, this circuit decodes a standard touch tone codes. The components R1 and C1 for each 567 chip should be computed according to the formula: f=1/(1.1 *R1 *C1). […]
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Kids like the police or fire-brigade cars siren sound. This circuit can generate dual tone like Police or Fire-brigade cars siren sound. This circuit usually installed on battery powered cars, bicycles, and motorcycles. Not only that, but also can be installed in models and other games. Here is the schematic diagram of the circuit: Basically, this circuit utilize the IC1A […]
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This is Hot Water Level Indicator circuit. This circuit can be used to monitor level of hot water in a tank. This circuit is simple and inexpensive. this circuit uses thermistors NTC1-4 as the sensor that is placed spread over the height of the tank. If the sensor is placed 4 inches from the top of the tank, it will […]
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This is a TV Remote Control Jammer circuit. Remote control use modulated light to combat eer infrared nvironment/background infrared noise. Your room heater, sunlight, incandescent lamp, and many other devices emit infrared. Without modulating the infrared carrier, other source of infrared will block the remote control signal, since the othsources are mostly strong enough. Since the remote control transmit IR […]
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