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IR (Infrared) Detector Circuit Diagram

Men in particular enjoy the convenience of television remote controls – often to the annoyance of their female partners. Men apparently want to know what they’re missing when the TV is tuned to a particular program, so they like to keep zapping to other channels. With the remote control in their hands, they feel like they are the lord and master of the TV set. They are thus completely at a loss if the remote control doesn’t work properly. There are many reasons why a remote control unit can malfunction, such as defective IR receiver in the TV set, a defect in the remote control, or empty batteries. Here a tester that can determine whether the remote control unit still emits an IR signal can come in handy. If you want to keep the IR reins firmly in hand, you can build your own IR detector.... [read more]

3 Band Equalizer

A classic circuit of regulation of tone of three way, with which we can regulate low, mid and high frequencies, of acoustic signal. The boost/cut can be regulated in the range of ± 18 dB/oct. In the circuit the supply is ± 15V, but can be also supplied with alone supply + 9 until + 30... [read more]

USB Power Injector For External Hard Drives

In fact, the device is powered from two USB ports, since one port is incapable of supplying sufficient current. That’s done using a special USB cable that’s supplied with the drive. It has two connectors fitted to one end, forming what is basically a "Y" configuration (see photo). One connector is wired for both power and data while the other connector has just the power supply connections. In use, the two connectors are plugged into adjacent USB ports, so that power for the drive is simultaneously sourced from both ports.... [read more]

Controlling a relay with a digital logic level.

The schematic illustrates 4 methods of controlling a relay with a digital logic signal.... [read more]

Geomagnetic field detector

This basic oscillator will detect the Earth magnetic field. The ferrite rod and coil are taken from an old Medium Wave receiver and a small magnet is glued at one end.... [read more]

Modular Class A Buffer preamplifier

A unit which is often very useful, if we need to isolate, in sound circuits, two stage between them. Then we can use this circuit which has an amplified unit, which gain X1, we do not use total negative feedback, only local, with the result that distortion remains at a very low level. Matching must be done with great care to the types of transistors, resistor between them.... [read more]