The simple circuit offers no isolation, but the simplicity of the circuit combined with cost of sound cards and the fact that diodes 1 and 2 add a good measure of protection makes this circuit ideal for the average user. Notice the physical hardware includes a 20MHz crystal oscillator module. This is not required to make the circuit work, but is i
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ncluded for calibration purposes. ( Stop the doubt before it makes you go batty ). The prescaler consists primarily of a down counter. AC coupling is provided together with a DC trigger adjustment. An opto coupler provides the signal isolation. The power supply could be a complete hybrid 5Volt to 5Volt isolation unit, or as in this case a component based design. The transformer used is a base drive transformer savaged from a 11W energy efficient lamp. If I remember correctly mine comes from a Phillips unit. The circuit is not particularly efficient, and as a result a simple shunt regulator can be used on the output. I use R9 to detect the shunting current. In my case it sits at 12mA.
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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