Phone-In-Use Indicator
Posted on Dec 19, 2012
New Circuits
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This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of.... -
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is.... -
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to.... -
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This.... -
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the.... -
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,.... -
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the.... -
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power.... -
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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Timing resistor R may be adjusted to any value between 10 K and 50 M to obtain a frequency range...
The tester provides an audible indication of the logic level of the signal presented to its...
In this circuit, a square wave is filtered by a high-order low-pass filter so that a -3-dB...
This is designed to work with a varity of stepper motors, 5 or 6 wire unipolar types. Its also...
This RF Wave Absorbion meter will detect signals between 10cms and 10m away all acording to the...
The Arduino microcontroller board is able to supply a current of 40mA from its output...
A meter is a measuring instrument. An ammeter measures current, a voltmeter measures the...
In this circuit, a simple calculator, in conjunction with a COB (chip-on-board) from an analogue...
A common-base Colpitts oscillator using a pnp transistor as the amplifying device. Notice in this...
The circuit can drive the companys Dialight 745-0005 monitor, which is a word composed of 64...
Consisting of integrated analog multiplier MC1596 synchronous detector as shown in FIG. The...
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