In appliance that appeal for aerial current, Nicad (NiCd) rechargeable array still has the angry achievement compared to NiMH and Lithium battery. The charger ambit actuality is acute in the way it handle the amiss polarity of the array placement. The core of this battery charger circuit is the Q2, configured a constant current source for the batt
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ery. LED D3 and zener diode D2 make the voltage applied to Q2 base constant, therefore the voltage and the current across R1 is constant. Using the value shown in the schematic diagram, the current flow through R1 will be constant at around 50 mA. You can see that the base of Q2 is supplied by R3, which is controlled by Q1. Look at the Q1 base, it`s controlled by the battery voltage, so Q1 won`t works if the battery is placed in wrong polarity. Just note that although this battery charger could charge four Nicad battery (in series), it can`t detect if one battery placed in wrong polarity while two or three other batteries are in right polarity. A small transformer, a bridge diode, and an electrolytic capacitor is needed to supply this circuit. Remember to provide a sufficient heat sink for Q2. This circuit will work as long as the battery is not completely discharged, because its weak voltage is needed to trigger the Q1 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....
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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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