When the amplifier is switched on, the speaker gets popped up by a high voltage and you can hear a loud thud sound from the speaker. This stuff is very harmful to the speaker and it drastically reduces the speaker`s life. The circuit shown here connects the speaker to the power amplifier output only after a few seconds the amplifier is powered ON.
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A simple transistor based time delay circuit is used for attaining the purpose. The circuit is so connected to the existing amplifier that, when the amplifier is powered on the bridge D1 also gets powered through the amplifier`s power switch. Capacitor C1 filters the output of bridge rectifier D1. When the power switch is made ON, the Darlington pair (Q1 and Q2) gets switched ON only after the capacitor C2 is sufficiently charged (to 0. 7V) through the resistor R1. Here the value of C2 and R1 are so selected that the time delay is around 2 seconds. So the relay gets activated only after a few seconds the amplifier is powered ON and until that time the speaker will be kept isolated from the amplifier`s audio output as the speaker is connected to the amplifier`s output through the N/O contact of the relay. During this initial delay period the output of amplifier will be grounded by the resistor R2 through the N/C contact of the relay. This is done in order to ensure that the DC blocking capacitor at the amplifier`s output is charged before it is connected to the speaker.
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....
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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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