January 2013

This month’s highlights

3 Input Stereo Audio Switcher

Add analogue audio inputs to your stereo amplifier or home-theatre set-up with this PICmicro powered audio switch.

It benefits from an IR remote control input to select the audio source or use one of the device’s pushbuttons.

Stereo Compressor

This stereo audio compressor lets you reduce the dynamic range of a sound source to more comfortable levels. Helps overcome the problem of e.g. noisy adverts or variable sound output levels between different radio stations.

It continuously adjusts the signal level by amplifying the quiet passages and attenuating the louder ones, so that the overall volume range is much reduced. Ideal for listening to TVs via headphones, also useful for PA systems and mood music.

Low-Capacitance Adaptor for DMMs

Using a standard digital multimeter you can measure capacitance from less than a picoFarad to over 10 nanoFarads with this special adaptor.

It allows you to measure tiny capacitors or stray capacitance in switches, connectors and wiring.

Universal USB Data Logger (Part 2)

Last month we described the main features of the USB Data Logger and provided the circuit details. In Part Two, assembly is described and we explain how to install the Windows driver and PC host software. We also discuss how the unit is used.

Jump Start

Our series for beginners and students alike offers an ipod speaker, easy to build, low cost and portable, with options to build your own enclosure.

Also in this issue:

Raspberry Pi keypad and LCD interface
Circuit Surgery – more notes on the Early effect.
Techno Talk – more news on the latest trends and developmewnts in electronics
PIC n MIX – getting to grips with Interrupts
Max’s Cool Beans blog
Practically Speaking – the practical aspects of identifying and using switches
Net Work – the Internet column discusses Netiquette and “showrooming”