The circuit is built using ICM7217 integrated circuit, manufactured by Intersil, which contains a CMOS counter up / down, with 4 digits and display properly. IC3 is the clock generator circuit which provides a square wave with period 1 s clock signal is available on pin 3 (Q13). It can be divided by 60 in IC4, if necessary, measurement of longer t
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han one hour. When S6 is closed, power is connected and IC1 is reset by R9 and C5. S4`s position determine if minutes or seconds are counted: not exceeding 59 h and 59 min (position 2) or 59 min and 59 s (position 1). Miniature switches S10 S7 adjusts the display to indicate 20. 00. In a short press of S3, this choice is stored by IC1. After that, S7-S10 is adjusted so that the display to indicate 35. 00. Meanwhile, S1 must be open. Pressing S2 cause of integrative ICM7217C start counting backwards, starting from 35. 00. When the display shows 20. 00, buzzer sounds shorter.
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....
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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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