Ultrasonic Movement Detector Circuit Project Battery operation is not recommended for this ultrasonic movement detector circuit. As the battery potential decreases the sensitivity will change. This is partcuarly so if the unit is triggered often (as in detecting a door opening.) It is better to use a power supply. Use 9V to 12V DC. You… Read More »
Home Telephone Call Recorder Circuit Project Today telephone has become an integral part of our lives. It is the most widely used communication device in the world. Owing to its immense popularity and widespread use, there arises a need for call recording devices, which find application in call centres, stock broking firms, police, offices, homes,… Read More »
Automatic Light Controller Circuit Project The circuit is simple and can be assembled on a small gene r a l -purpos e PCB. Use a heat-sink for IC1. Make sure that LDR1 and the light bulb are well separated. The circuit can be used for streetlights, tubelights or any other home electrical lighting system that… Read More »
Four Stage FM Transmitter Circuit Project This transmitter is meant only for educational purposes. Use of this transmitter with outdoor antenna is illegal in most parts of the world. The author and EFY will not be responsible for any misuse of this transmitter.
Long distance IR transmitter circuit document Here is a simple circuit that will give you a pretty long range. It uses three infrared transmitting LEDs (IR1 through IR3) in series to increase the radiated power. Further, to increase the directivity and so also the power density, you may assemble the IR LEDs inside the reflector… Read More »
Color detector scheme diagram When all of the LDRs get triggered or stay untriggered, you will observe white and black light indications respectively. Following factors might be carefully noted: Potensiometers VR1, VR2 and VR3 may possibly be applied to alter the sensitivity of the LDRs. Use good quality light filters. Common ends of the LDRs… Read More »
Lab Note: The COBs used in different watches may differ somewhat in their configuration. But by trial-anderror one can always find out the appropriate points corresponding to points A, B, C and D. Figure of a second COB used by EFY Lab is shown alongside. The points A and B (on the COB used by… Read More »
The ADC0808, ADC0809 data acquisition component is a monolithic CMOS device with an 8-bit analog-to-digital converter, 8-channel multiplexer and microprocessor compatible control logic. The 8-bit A/D converter uses successive approximation as the conversion technique. The converter features a high impedance chopper stabilized comparator, a 256R voltage divider with analog switch tree and a successive approximation… Read More »
Angry Beard 3 Guitar Effect Circuit Diagram and PCB Layout