01 May 2009

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.

18 April 2009

You might not be aware of it but your digital multimeter is unable to make accurate current measurements in low-voltage circuits because of its "burden voltage". This precision current adaptor solves that problem and greatly improves the measurement accuracy, as well.

16 April 2009

Our introductory second-generation UHF data transceiver article in October 2008 showed that using a PICAXE to drive HopeRF's HM-TR 433MHz programmable data transceivers works well. In subsequent months, these well-priced units have become very popular!

14 April 2009

This simple device allows two computers to share a single USB printer or some other USB device, such as an external flash drive, memory card reader or scanner. A rotary switch selects the PC that you wish to use with the USB device, while two LEDs indicate the selected PC.

12 April 2009

The Tektronix MS2024 is a compact mixed-signal oscilloscope that is suitable for a wide range of applications or educational use. It has four analog and 16 digital inputs, a sampling rate of 1Gs/s and an operating bandwidth up to 200MHz. It is very easy to use and does not take up a lot of valuable bench space.

08 April 2009

Have you been booked for driving through a school zone at well above the 40km/h limit? It's easy to do and can be a very expensive mistake. Here's a project to help you stay out of trouble. It keeps track of the time and flashes a warning LED during the morning or afternoon 40km/h time periods.

06 April 2009

Connecting Puppy Linux to the Internet via a network cable is a piece of cake. Wireless networking can be slightly more difficult but is still easy to do. Here's how.

04 April 2009

You probably think that a dimmer is a dimmer is a dimmer, right? This little beauty will definitely change your mind!

02 April 2009

Last month, we discussed the details of the Advanced Audio Coding (AAC+) used in Digital Radio. This month we discuss how the AAC+ data is transmitted and received. The transmissions combine data with program content and the entire transmission is a multiplexed combination of the many programs.

22 March 2009

Versatile unit indicates signal levels in mV, dBv & dbm

Want to measure small signals at audio frequencies? Here's a low-cost digital audio millivoltmeter which will allow you to measure audio signals from below 5Hz to above 100kHz. As well as indicating the level in both millivolts and dBV, it also shows the corresponding dBm level into 600 ohms.