Free Simple Circuit Diagram
Using a dual-colour LED and few surrounding components, we can make a very simple battery monitor. This battery monitor circuit is suitable for monitoring your car battery, enrich your dashboard with cool and functional accessory. Orange colour is produced by LED when the red and green LEDs are illuminted. The red LED illuminates below 10.5v, green LED illuminates above 11.6v, […]
Read moreWe can use this basically a high gain amplifier with feedback circuit to cause the LED flash at rate determined by the 10u and 330k resistor. Before insert the unknown transistor, remove one of the transistor. The LED flash when it’s NPN with pins as shown in the photo. Remove one of the transistors to turn the unit off. [Source: […]
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All types of transistors including Darlington and power will be tested in this project. Connect the 9v battery around the other way at points A and B to test PNP types. The transformer in the photo is a 10mH choke with 150 turns of 0.01mm wire wound over the 10mH winding. Then, the two original pins (with red and black […]
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Below is a comparator circuit which is can measure with step of 1 volt, the voltage of car battery. The indication of voltage is done by comparison of battery voltage with the reference set by D1. This voltage is applied to the inverting inputs of amplifiers with to compare the battery voltage. We can regulate the gradation of voltage that […]
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