If both the reading are high then the diode is short. If both the readings are Low then the diode is open. If any of read pins are low and the second is high then the diode is good. This concept can be easily extended to test a transistor by realizing that a transistor consists of two PN junctions: one between the base and the emitter (BE junction
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), and the another between the base and the collector (BC junction). If both the junctions conduct in only one direction, the transistor is normal, otherwise it is faulty. We can also identify the type (PNP or NPN) of the transistor by considering the direction of the current conduction. Three I/O pins of a microcontroller are required to implement the testing algorithm for a transistor. 2. Set D1 High and read D2. If D2 is High, EB junction conducts, otherwise not. Set D3 High and read D2. If D2 is High, CB junction conducts, otherwise not. Now, if only the BE and BC junctions conduct, the transistor is of NPN type and is working fine. And, if only the EB and CB junctions conduct, the transistor is still normal but the transistor type is PNP. All other cases (like EB and BE both conduct, or BC and CB both not conducting, etc. ) indicate the transistor is not good. This project gives an idea that how we can interface the keypad and & Segment Display with PIC Microcontroller. When we press any digit from keypad, it will be displayed on the seven segment display. By pressing the # key, digit will increment and by pressing the * key, displayed digit will be decremented. 7 Segment Displays are of two types. Common Anode and Common Cathode. In Common Anode type display, Anode of each segment of display is common and we connect it to the Vcc or +5V. Whereas, cathode of each segment is available on the physical pins of 7 segment...
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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