May 2026

Net Work

Our periodic column aimed at Internet users and hobbyists this month describes problems with the CTEK ‘smart’ battery charger, suggests a USB adaptor that triggers higher voltages from a 5V ‘PD’ power adaptor or powerbank,  and gives a timely warning about changes looming in import duties that will affect many constructors who import parts from overseas. The author also considers the merits and pitfalls of Temu, one of the world’s largest e-commerce destinations.

Weird & Wonderful Arduino Projects
Part 17: Chronological contraptions and solid snakes

Development of Max’s Arduino-powered retro games console continues with more code,  hints, tips and insights as the project continues to take shape.

The Fox Report

Barry Fox brings us right up to date with the development of the Freely TV platform in Britain, citing some fundamental features of the new platform that are buried deep in the small print. Barry shares some useful comments from Humax and Manhattan. If you’re thinking of buying a Freely TV or set-top box, this article is a must-read.

Teach-In 2026
World of Wireless – an introduction to Radio and Wireless Technology

Part 7: Spectrum and vector network analysis

This exciting primer about modern radio and wireless technology continues by focussing on techniques for analysing RF networks and devices, including S-parameters, vector network analysis and spectrum analysis. This month’s practical project that you can build yourself is a 5W load and power meter.

SSB Shortwave Receiver
(Part 1)

This analogue single-side band (SSB) radio receiver is designed for SW reception and uses modern surface mount techniques with an LCD display to form a radio offering decent quality reception. Part 1 this month describes the fundamentals of the sophisticated circuitry.

Circuit Surgery

The topic of measuring circuit frequency response using a PC sound card continues with more details of op.amp compensation. Illustrated with LTspice simulations.

433MHz Transmitter Module

This 433-434MHz LPD433 (low interference potential device) module design allows hobbyists to construct a compliant remote control device that is a direct drop-in replacement for commercial designs. A receiver module is described in next month’s issue.

Audio Out
Part 2: All-pass filters – time delays from audio filters

Our exceptionally insightful analog audio expert covers the topic of all-pass filters, techniques that are very useful for time alignment compensation in loudspeakers. Details of actual commercial examples are included.

Tool Safety Timer

Avoid the risk of accidentally leaving a soldering iron or other mains powered unit switched on, with this PIC-powered safety controller. It uses a PIR to detect user movement and powers down the mains should a period of inactivity be detected. (Photo shows project built into a hot air rework station.)

Techno Talk

From the earliest days of the 8-bit microprocessor to today’s Arduino single-board computers, Max reflects on the astonishing evolution of modern computing.

Power Electronics
Part 2: Controlling DC-DC converters

Last month, we introduced average value analysis and used it to analyse a range of DC-DC converter topologies at a high level. This month we explore the control systems required to make these converters work correctly.

Next month

RGB LED ‘Analog’ Clock; USB Power Adaptor; DIY LPD433 Receiver Module.