July 2026

RP2350B Development Board

This feature introduces readers to the bigger sibling of the Raspberry Pi Pico 2, the RB2350B Development Board. It’s faster, has more pins, more I/O, more storage and memory. It’s perfect for breadboarding experiments too, and can be purchased  pre-assembled.

Audio Out
All-pass filters (Part 4)

Continuing with the theme of all-pass filter design and construction, this month new PCBs for an 8-gang pot and an improved polarity-reversal switch are offered, along with a précis of the Symmetra-Peak broadcast-standard symmetriciser and similar models. There’s some seriously bad news about the ubiquitous NE5532 as well.

USB Solar Charging

This simple constructional idea allows you to charge and power all your USB devices from a low-cost solar panel system. A basic outline with suggestions for experimenters to try out for themselves.

Smart Probe

This very sophisticated constructional project is an extremely handy device that’s ideal for making voltage and continuity measurements. Thanks to the use of surface-mount components, it’s extremely compact in size and will soon become the hobbyist’s ‘go-to’ gadget when performing initial tests. An OLED display and internal buzzer complement a host of features, making it ideal for testing continuity and voltages up to 50V, as well as diodes/ LEDs. The ultra-low power design uses an accelerometer to detect orientation and (lack of) movement, so it’s always ready for use. The Smart Probe is a superb piece of test equipment for the advanced electronics enthusiast to build.

Circuit Surgery
Measuring frequency response using a PC sound card
Part 10: differential amplifiers and line drivers.

We continue the topic by exploring differential line drivers and also consider differential receivers, including practical implementations of both.

Techno Talk

Max meanders down memory lane, recounting the evolution of printed circuit board design, CADding and modern software-driven AI technologies.

Mains Earthing Systems

The earth (or ground) is an integral element of electricity distribution systems everywhere. This special feature examines different earthing systems used around the world and explains the nomenclature associated with them.

Weird & Wonderful Arduino Projects
Part 19: ‘Marble mayhem and tilting tomfoolery’

An inertial measurement unit (IMU) is tasked with the job of  detecting the tilting attitude of Max’s retro games console.

Teach-In 2006
World of Wireless – an introduction to Radio & Wireless Technology
Part 12.9: RF Sources and oscillators

The latest instalment of our educational primer takes a deep dive into RF sources, explaining how to get the best out of phase-locked loops (PLLs), direct digital synthesis (DDS) chips and more besides. This month’s practical project is an accurate calibration source and programmable frequency marker.

Power Electronics
Part 4: AC-DC Conversion using Rectifiers

This month’s feature explores the operating principles of these deceptively-simple looking circuits.

The Fox Report

Barry Fox is an early adopter of ‘balcony solar’ kits that are due to arrive in Britain this year. These simple DIY solar panels promise to help boost a household’s domestic baseload for little cost, but Barry tries an imported model and highlights the possible pitfalls that they may have.

Next month

USB-C Power Meter; Home Automation Satellite; RP2350B Computer.