A variety of small school projects can be built using just two transistors. This compilation includes a collection of practical and fascinating circuit ideas using just a few number of parts. Any small signal transistor can be used in the proposed two transistor circuit, such as BC547, 2N2222, 2N2907, BC108, BC107, TIP32, TIP31, 188, 8050, […]
Transistor
Transistor Multivibrator Circuits [Astable, Bistable, Monostable]
A transistor or BJT multivibrator is a two-stage switching circuit that is configured in a cross-coupled manner. This allows each of the active BJT stages to be regeneratively cross-coupled with the other BJT stage, so that one switches ON when the other switches OFF, and vice versa. This cross-coupling may be set up to switch either a […]
Variable Voltage, Current Power Supply Circuit Using Transistor 2N3055
In this post I have explained how to make a simple variable power supply circuit using transistor 2N3055 and some other passive components. It includes variable voltage and variable current feature, fully adjustable. Main Specifications 1) Adjustable from 0-30V, 0-60V, and 0-100V, and 500mA to 10 Amp as per user preference 2) Short Circuit Protected […]
Match Transistor Pairs Quickly using this Circuit
In many critical circuit applications, like power amplifiers, inverters, etc it becomes necessary to use matched transistor pairs having identical hFE gain. Not doing this possibly creates unpredictable output results, such as one transistor getting hotter than the other, or asymmetrical output conditions. By: David Corbill To eliminate this, matching transistor pairs with their Vbe […]
Bipolar Transistor Pin Identifier Circuit
In the proposed BJT pin identifier circuit when the circuit is switched on, two jumpers will have both LEDs ON and the third will have only one LED illuminated. Investigated, Modified and Written By Abu-Hafss The E-B-C, NPN/PNP Detector Concept The jumper with one LED ON is connected to BASE. If it is red LED, […]