
This circuit is a simple buzzer circuit and it called novel buzzer. It only uses a relay in series with a small audio transformer and speaker. The relay will operate via the transformer primary and closed relay contact, when the switch is pressed. The normally closed contact will open as soon as the relay operates, [...]
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ROHM (www.rohm.com) is originally a resistor producer company, but finally expand their business and produce monolithic IC, and this one used in our circuit is the example. The internal structure of this FM transmitter integrated circuit consist of stereo modulator that creates a stereo composite signal, an FM modulator that modulate a carrier frequency with [...]
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Many new computers now only has USB port, and this serial to USB adapter might be the only help for old devices that provides only RS232/COM Port. This serial adapter uses FT232 USB-RS232 converter IC from FTDI (Future Technology Devices International). The main features of this USB serial adapter chip are: 384 [...]
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Stepper motor gives a simple, low cost, and accurate position control. Stepper motor can be driven by circuit mounted close to the motor, and controlled by a remote control circuit through long cable. The interesting thing of this circuit is that the power for both motor and the driver circuit is carried over two wires, [...]
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