Telephone Hold Line
Posted on Sep 21, 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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This regulator is suitable for devices that need up to 1mA. For higher output current, the...
The frequency doubler uses only one !C. Like other doublers, this circuit uses both the rising...
This system will alert you or anyone chosen by automatically dialing a programmed phone number....
LED light chaser circuit typically refers to an electronic configuration able to generate or...
With simplicity being the goal, brain-wave goggles can be constructed from suitable eyewear, such...
The bi-directional sequencer uses a 4 bit binary up/down counter (CD4516) and two "1 of 8 line...
This circuit is a modified Hartley oscillator with a couple of extra components included. The...
This circuit features automatic Exit and Entry delays and a timed Bell Cut-off. It has provision...
This is a simple microphone preamplifier circuit which you can use between your microphone and...
Although a distribution amplifier may accept different input channels and output those to...
Circuit works: When normal inspection work where the voltage across the resistor R2 through, RP,...
The circuit amplifier and an attenuator control video detector consists of a composition for...
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