Telephone electronic lock circuit
Posted on Dec 11, 2010
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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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The remote control transmits encoded signals. Each time a key is pressed, the relevant code is...
Most small portable radios require a 3-V supply, which is normally provided by two AA or AAA...
Triac regulation suited to regulate the power of mains appliances. It can regulate the brightness...
The key board here we are interfacing is a matrix keyboard. This key board is designed with a...
I have been working on driving an analog VU meter based on the sound going out the Raspberry Pi`s...
This circuit creates a stunning display of the "magic" of magnetism by suspending a small metal...
A nice schematic for an lm3915 VU meter. I have attempted to create a band pass filter in order...
The PLL transmitter exciter has the functions of providing a stable, low noise,...
This dc voltage doubler circuit produces a voltage that is twice its voltage supply. This is...
The Atmel AVR series are very good microcontrollers with quite a rich instruction set, rich...
Most sound card microphone inputs require a minimum signal level of at least 10 millivolts, but...
As shown in Figure 4 hours AC timing circuit. In this circuit, BH4024 is 7 serial binary...
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