March 2025

The Pico Gamer

This handheld games console was originally inspired by the highly popular Nintendo GameBoy first seen in the late 1980s. Our 21^st century inspiration is a PicoMite-powered retro games machine that runs no less than nine games, including a Tetris lookalike, and Pac-man and Space-Invader style version. With a colour 3.2” screen and rechargeable LiPo battery, it’s housed in a 3D-printed case and there’s enough here to keep you entertained for hours.

Compact Frequency Divider

This small board converts a standard 10MHz frequency response (eg derived from an oscilloscope) to 1MHz and 1Hz square waves. The latter can emulate the 1PPS output of a GPS receiver, and there’s options for a 10% and 50% duty cycle. A surface-mount design project.

Mains Power-Up Sequencer (Part 2)

This sequencer is designed to solve problems that can occur when switching on multiple mains-powered circuits or appliances. It can overcome circuit breakers tripping or speaker ‘thump’. It can handle up to four devices but can be daisy-chained to handle 8, 12 or even more. In Part 2 this month, the project’s constructional details are described along with all necessary interwiring diagrams.

Warning! For experienced constructors only. The entire circuitry of the Mains Sequencer operates at mains voltage.

Precision Electronics (Part 3)

In this third article, our precision current-measuring circuit is developed further. We also consider how to sense the current inline in a positive rail.

Max’s Cool Beans: Weird & Wonderful Arduino Projects
Part 3: building a 14 x 10 tricolour LED array

Continuing the theme of shaping a 144 tricolour LED strip into a 14 x 10 array that will form the display of Max’s retro games console.

Audio Out

Our column for analogue audiophiles returns this month, with an intensive discourse on the ins and outs of using capacitors in hi-fi applications.  A multitude of photos and diagrams offers readers a veritable feast of interesting facts!

The History of Electronics (Part 3)
Inventors and their Inventions

This part highlights key developments in electricity and electronics during the years 1848 to 1881. A fascinating article that spans decades of developments, including many discoveries by inventors whose work fuelled today’s technology.

Harold S. Black: Negative Feedback and the History of op.amps

All about Op.amps recounts the development of one of the most significant early circuit principles. Now discovered nearly a century ago, the idea of negative feedback would have a profound and immediate impact on analogue circuit design techniques.

Also in this issue:

• Techno Talk: Max expounds on the frightening capability of real-time AI-enabled holographic personæ.
• The Fox Report Barry shares his practical experiences after suffering the pitfalls of trying to upgrade from Windows 10 to Windows 11.
• Net Work This month’s roundup of what’s happening in the world of space and technology focuses on the UK’s program to provide launch facilities for LEO satellites. We check out NASA’s latest achievements as well.
• Circuit Surgery Advanced topics in digital signal processing (DSPs) continue this month, with a look at windowed sync filters.

Next month

Skill Tester 9000 wire & buzzer game; ESR OLED Test Tweezers; Linear Fan Controller. Contents may be subject to last minute change.