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555 Fast Reset Timer

Jim Keith — Fri, 17 May 2013 06:16:03 +0000

A common problem with on-delay timers is the timing capacitor reset. Typical timers (555 included) rely upon both complete power loss and finite elapsed time to assure that the timing capacitor is fully discharged. If this important detail is ignored, the timeout period is reduced and inconsistent. This 555 timer circuit resets almost instantly when [...]

Source: 555 Fast Reset Timer

Infrared Model Train Detector

T.K. Hareendran — Wed, 08 May 2013 11:01:48 +0000

This simple and economical IR model train detector circuit is intended especially for those hobbyists who wish to add a smart sensor to detect trains on their model railway track. As can be seen in the schematic diagram, it comprises of a simple infrared transmitter and receiver wired around the good old PLL Tone Decoder [...]

Source: Infrared Model Train Detector

LM567, NE567, SE567 Datasheet

Popescu Marian — Wed, 08 May 2013 10:58:50 +0000

The LM567, NE567 and SE567 are general purpose tone decoders designed to provide a saturated transistor switch to ground when an input signal is present within the passband. The circuit consists of an I and Q detector driven by a voltage controlled oscillator which determines the center frequency of the decoder. External components are used [...]

Source: LM567, NE567, SE567 Datasheet

Top 10 Electronic Projects of April 2013

Popescu Marian — Wed, 01 May 2013 07:21:56 +0000

It is time to show you the April 2013 top 10 of electronic circuits from electroschematics.com. April was a great month with new projects published on regular basis and on Facebook we are almost 10.000 friends. Top 10 Projects Automatic battery charger A 12 volt lead acid automatic battery charger that shut off the charging [...]

Source: Top 10 Electronic Projects of April 2013

PIC12F635 Based Door Alarm System

T.K. Hareendran — Tue, 30 Apr 2013 07:21:36 +0000

Now you can build your own simple door alarm security system using a tiny microcontroller chip PIC12F635! The circuit is nothing but an aural alert unit, which raises a warning tone when the concerned door is opened by someone. You can install this unit in your front/back door as a security alarm to deter burglars [...]

Source: PIC12F635 Based Door Alarm System