Privacy in parallel telephone line
Posted on Nov 15, 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 charger will quickly and easily charge most any lead acid battery. The charger delivers full...
It is a relatively simple circuit, with which we can have optical and sound clue, when we have...
The circuit uses Ql to buffer the right-channel balance output while Q2 and Q3 form a VOX...
The PCB for this amplifier can be purchased from Spare Time Gizmos for $16US. In a single...
The circuit even has a current limiting feature which is a more reliable system than most...
Many integrated circuits have undocumented features or abilities. This is one of them. The TLC555...
This Alarm will help you with its loud Police siren to abort the attempt of intrusion. With a...
This light activated relay circuit presented here uses the 555 timer IC and a light dependent...
Most sound card microphone inputs require a minimum signal level of at least 10 millivolts, but...
Before you can design an adjustable voltage regulator into your circuit, or do a redesign, you...
Powering up my twin digital Sony DSC-V1 cameras at exactly the same time frequently synchronizes...
This is a simple circuit which outputs a voltage which is more than the input. This could be used...
This mic preamp uses the low noise IC uA739. The circuit is an example of how a good preamplifier...
Electric sewing machine saving circuit as shown, line the main elements by the Hall switch IC IC...
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