The IN914 (little glassy diode) and the zener diodes all have bands on the body which must be put in the direction shown on the drawing. The bands ar ` e at the K end of the diodes. A magnifying glass will help to locate the bands and also to check the values of the zeners. To identify them, the following procedure will help : with a magnifying
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glass find the diode that` has the code IN4148 printed on the glassy surface. This is the silicon diode usually referred to as IN914, NOT a zener. The zeners may have their voltage printed on the side, or they may have numbers. Remember that there are two 6V8 zeners and one 11V, so 4. The molex pins are to connect the wires to the circuit. Push them through in their holes and solder. Bare the Red and Black hook-up wires, tin them and solder to the pins. Red is Positive, Black Negative 5. Connect the circuit to a power supply with a variable Voltage control, but make sure the polarity is co ect. Wind up the voltage and check the performance of your circuit against the quoted performance figures. This circuit depends for its operation upon the different voltage drops across different colour LEDs. At 20mA the voltage drops across red, yellow and green LEDs are typically 1. 7, 3. 0 and 2. 3 volts respectively. When the vehicle battery voltage is too low to cause either ZDI/ZD2 or ZD3 to conduct, Q1 and 02 are held off by R3 and R5. Under these conditions the yellow LED is forward biased and conducts `via D1 producing a potential of about 3. 7 volts at the "A legs" of the LED`s. When the supply rises above about 11. 6 volts ZD3 conducts, biasing Q2 on. By virtue of its lower voltage recuirements the green LED conducts, reducing the voltage at the "A legs" of the LED`s to approximately 2. 6 volts. This is not enough to bias...
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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