Welcome!

This circuit is a small +5V power supply, which is useful when experimenting with digital electronics. Small inexpensive wall tranformers with variable output voltage are available from any electronics shop and supermarket. Those transformers are easily available, but usually their voltage regulation is very poor, which makes then not very usable for digital circuit experimenter unless a better regulation can be achieved in some way.... [read more]

The fixed voltage power supply is useful in applications where an adjustable output is not required. This supply is simple, but very flexable as the voltage it outputs is dependant only on the regulator and transformer you choose.... [read more]

We've called it the Itsy Bitsy USB Lamp. It is such a delightfully simple idea we're wondering why no-one ever thought of it before. It started life (and continues) as a student project at Massey University in Wellington, New Zealand - and in fact was submitted to us by the lecturer, Stan Swan. When we say simple, we mean it: just a USB plug on a suitable length of cable, a super bright white LED and a series resistor to limit LED current. The LED and resistor are housed in an in-line fuse holder (without its innards!) which makes a superb little "wand" and also protects the electronics, such as they are.... [read more]

This simple circuit generates narrow pulses at about 700-800Hz frequency. The pulses, containing harmonics up to the MHz region, can be injected into audio or radio-frequency stages of amplifiers, receivers and the like for testing purposes.... [read more]

It's based on a Philips class-H audio amplifier IC and can deliver 36W RMS OR 70W music power, all from a 13.8V supply. Our new Mighty Midget Amplifier can really pack a punch - around 36W RMS continuous into a 4-ohm load when using a 13.8V supply. However, it's the 70W of output power that it can deliver during dynamic (music) signal conditions that really make you sit up and take notice.... [read more]

The aim of this design is to reproduce a Combo amplifier of the type very common in the sixties and the seventies of the past century.... [read more]