Basically, this is a frequency-current converter. It is used as frequency meter. Calibrating it can be used as tachometer. Please be aware this is an experimental project, I didn't use it connected on any vehicle but it should work fine after calibration. It can be connected directly to the voltage from the car. The input signal can be connected directly to any source of frequency. I believe it will work fine if it is connected directly to the spark plug line. Be sure not to use germanium diodes for this one. Any silicon diode should work fine. The diodes at the input reduces the voltage to a safe level ( 0.7 Volts). DO NOT CONNECT the circuit without doing the calibration first.
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The bridge diode that is connected to the miliamperimeter can be replaced by 4 silicon diodes as the picture shows. The miliamperimeter can be replaced by a multi-meter set to measure mA. To calibrate this circuit first: Adjust R1 and R2 at the middle point. Apply power (12 Volts) and apply 60Hz at the input signal. Adjust R1 until it measures 0.360 (3,600 RPM) Stop the signal (0 hz) and adjust R3 until the meter indicates 0. Apply 60Hz again and adjust R1. If the meter doesn't show "0" at 0Hz and 0.36 at 60Hz, adjust R2 and repeat the calibration.
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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