An electrically isolated variable transformer is actually an obligatory piece of equipment in every electronics lab. However, many people are put off by the high price of such a device. In a... Read more
This LED flasher is made up of just five components and is an ideal circuit for novices to experiment with. Operation of the circuit is quite easy to understand. With a battery connected to... Read more
The low dropout voltage regulators from the LM2931 series are not just useful for powering microcontroller systems — they can also act as a low-frequency (practically) random noise generator... Read more
A noise generator with a wideband output signal is always handy to have around when you’re adjusting receivers and other types of HF equipment. The noise generator circuit described here use... Read more
The circuit depicted here forms one half of a device that will prove extremely handy when tracing the path of electrical wiring in a building or to locate a break in a wire. The system is ba... Read more
This circuit is designed to provide a wideband digital sine wave signal source. Its main feature is that because it synthesizes the signal in 32 steps, no low-pass filter is required to supp... Read more
The sound generator shown here uses its built-in loudspeaker as a microphone when it is in the standby state. As soon as it detects a noise that exceeds an adjustable threshold level, it bec... Read more
The generator is based on a Type 4006 quadruple shift register, IC1. Two of the shift registers are four bits long, the other two, five bits: a total of 18 bits. Only the clock is common to... Read more
The tester generates two different ” signals for checking a digital storage oscilloscope. The first is a stepped voltage on to which glitches are superimposed. The second is a rectangu... Read more
Noise generators are used for measuring the self-noise of amplifiers and receivers and for some acoustic measurements. The noise of traditional low-frequency noise generators is based on the... Read more