60-Hz, This high-Q notch filter is based on the `Twin-T` design. It produces a very deep notch in the response curve at about 59. 7 Hz. This is useful to remove 60-Hz hum and noise from audio recordings or live performances. Response is down over -60db at the center point, pdf file 8 Note Tune Player This neat little circuit can
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play 8 note tunes at any speed you want. You select the notes with 8 trim pots. The speed in selected through a ninth pot Adjustable 60Hz Filter On this page three adjustable notch filters configurations are shown. They can be used in your small pre-amp or amplifier project to filter out any HUM at 50 Hz ( European ) or 60Hz Audio amplifier output relay delay the purpose of this circuit is to control the relay which turns on the speaker output relay in the audio amplifier. The idea of the circuit is wait around 5 seconds ofter the power up until the spakers are switched to the amplfier output to avoid annoying "thump" sound from the speakers Audio circuits audio circuits, 2 Watt Amplifier A low distortion amplifier using discrete components, ECM Mic Preamplifier A high quality preamp for electret mic inserts, Tone Controls, Stereo Line Driver, TDA2030 8 Watt amplifier, Audio Notch Filter For audio frequencies 100Hz - 10KHz, 6 Input Mixer 3 Mic inputs, 3 Line Inputs, Hi-Fi Pramplifier, Peak Reading Audio Level Meter, Doorphone Intercom Music to light modulator A music-to-light modulator is a circuit which controls the intensity of one or more lights in response to an audio input, MOC3021, pdf file Siren circuit Emergency Siren Simulator, The heart of the circuit is the two transistor flasher with frequency modulation applied to the base of the first transistor, .
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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