01 August 2008

The 300MHz DPO3034, with its wide "digital phosphor" LCD screen, is a serious oscilloscope with an impressive list of features and an excellent user interface.

18 July 2008

If Swan's 2nd Law is: "Microcontrollers can never have too many I/O channels" . . . what's his first?

16 July 2008

Would you like to connect a stereo amplifier in "bridge mode" in order to deliver double the power to a single loudspeaker system? This simple adaptor allows you to do it, without any modifications being necessary to the power amplifiers themselves.

14 July 2008

Want to connect a professional microphone with balanced outputs to the line input of your PC's soundcard or an MP3 player, for high-quality voice recordings? This microphone preamp circuit lets you do just that. It features a balanced input, has a clipping indicator LED and can be powered from a USB port or from an external DC source.

12 July 2008

This compact device will help you tune almost any musical instrument - acoustic or electronic. It can produce any note on the tempered musical scale (standard pitch) in any of the eight most commonly used octaves, with an accuracy of better than ±0.08% or 1.3 musical cents. The selected note is compared with that from the instrument either by ear or visually by using an eight-LED stroboscopic beat indicator.

10 July 2008

10 July 2008

Developed during the very early days of radio, reflex circuits were used in receivers right up until the 1950s. One such set was the Astor KM.

05 July 2008

In last month's first part, we described the circuit operation of the DSP Musicolour. In this instalment, we guide you through the construction. The operation of the firmware and troubleshooting tips will be described next month. In this issue there are also notes and errata for the schematic published last month.

05 July 2008

Interesting circuit ideas which we have checked but not built and tested. Contributions from readers are welcome and will be paid for at standard rates.

02 July 2008

A light switch is a light switch, right? You just flick it and the light comes on . . . Of course - but it is very obvious that many people think what goes on behind the architrave or wall is a black art. Magic, even!