Circuit Digest

Joule Thief Circuit: A Low-Power Voltage Booster

This resource provides clear explanations of how switching regulators work and how voltage boosting is achieved efficiently ...
EDN

Simple two-transistor circuit lights LEDs

A previous Design Idea describes a circuit that uses an astable multivibrator to drive an LED (Reference 1). The circuit in Figure 1 uses a simpler alternative approach. The circuit uses a 2N3904 NPN ...
EDN

Basic Characteristics and Application Circuit Design of Transistor Couplers

Photocouplers optically links, via transparent isolating material, a light emitter and a photodetector. Used as an interface between circuits with different ground potentials, photocouplers replace ...
Electronic Design

Simple Electronic Lock Uses Single-Transistor Circuit

A very simple but highly efficient combination lock circuit is shown in the figure. Any type of on/off switches can be used, varying from commercially available inexpensive types to more sophisticated ...
Electronic Design

Simple Transistor Switch Detects Thermocouple Fault Conditions

Thermocouples and their leads often have to detect open-circuit or short-circuit faults. However, it is very difficult to distinguish a valid millivolt temperature signal from an open/short-circuited ...
elektormagazine

In-Circuit Transistor Tester

46 IN-CIRCUIT TRANSISTOR TESTER by A. Rigby In electronic troubleshooting a transistor is generally not above suspicion until it responds correctly to the usual diode-tests with an ohmmeter. Before ...
elektormagazine

Tube to Transistor: A Look Back at 1960s-Era Tech

The Basic Electronics book series (1959) helped spark Dr. Richard Honeycutt's fascination with tube circuits and transistors. Here he reflects on the transition from tubes to transistors. In 1960, ...