Random circuits

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Infra-red Level Detector

This circuit is useful in liquids level or proximity detection. It operates detecting the distance from the target by reflection of an infra-red beam.... [read more]

A Low Power Wireless Audio Power Amplifier

Using this low-cost project one can reproduce audio from TV without disturbing others. It does not use any wire connection between TV and Loud Speaker. In place of a pair of wires, it uses invisible infra-red light to transmit audio signals from TV to Loud speakers, Without using any lens a range of up to 6 meters is possible. Range can be extended by using lenses and reflectors with IR sensors comprising transmitters and receivers.... [read more]

Micro Power AM Receiver

Micro Power AM Receiver... [read more]

Frequency Divider with 7490

Here you will find a interesting collection from frequency dividers with division factor from 2 until 10. All the choices they are based in the 7490 that are a Decade and Binary Counter.... [read more]

Doorbell for the Deaf

This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch can be moved from within the house which will light a lamp in the door bell switch. The lamp can illuminate the words "Please Wait" for anyone with walking difficulties.... [read more]

100W Inverter Circuit Schematic

Here is a 100 Watt inverter circuit using minimum number of components. Here we use CD 4047 IC from Texas Instruments for generating the 100 Hz pulses and four 2N3055 transistors for driving the load. The IC1 Cd4047 wired as an astable multivibrator produces two 180 degree out of phase 100 Hz pulse trains.... [read more]