April 2024

This month’s highlights

Basic RF Signal Generator

This project will form a handy part of the constructor’s test gear line-up, being a basic signal generator offering 10Hz to 25MHz. It utilises a ready-made AD9834-based DDS module along with an Atmega microcontroller. An OLED display completes the specification.

Please Take Note : the article contains important updates regarding sources for the AD9834 module.

Automated “Swiss Army Knife” Test Bench

This handy “Swiss Army Knife” of test gear can provide test voltages, test signals, vary a resistance, switch a component in or out of circuit and even measure some voltages. It’s based on an ESP32 Wi-Fi controller and offers an array of useful functions for the hobbyist, including a 0-10V output, a variable signal generator, 3.3V rails, a relay, a web interface and more besides. The Automated Test Bench ties into automation software so it can perform tests automatically and log the data for subsequent analysis.

Silicon “Chirp” Cricket Novelty

This electronic novelty is fabricated in the shape of a cricket and will be a great source of amusement – keep it for yourself or prank a family member or friend by hiding it in their room. When they switch the lights off, they can get a bit of a chirping surprise! It can also produce frog or canary sounds. It has flashing red ‘eyes’ and is coin cell operated, having just a tiny quiescent current. The Silicon Chip uses a PIC 16F micro and is also a good introduction to trying some surface-mount soldering.

The article contains important warnings about coin cell batteries, and this design includes a battery retention device to prevent tampering or accidents involving children.

Teach-In 2024 (Part 2)
Learn electronics with the ESP32

The second part of this ESP32 primer takes a more detailed look at digital I/O and shows how to interface buttons and switches. The tutorial shows how to drive loads such as LEDs or relays, and there’s an introduction to the Serial Monitor. If you’re keen to get started with the ESP32, then Teach-In 2024 is for you!

Also in this issue:

Techno Talk – Max drools over the prospect of the latest VR headsets and technologies
Net Work – our monthly columnist tries Temu for the first time, snapping up a Bluetooth label printer for a bargain price, plus the Tapo range is explored and there’s a roundup of the latest nuclear energy news in Britain.
Circuit Surgery – Part 2 of an in-depth tutorial investigating the application of LTspice and frequency response analysis.
Max’s Cool Beans – Arduino Boot Camp (Part 16) tackles more 7-segment LED goodness in this Arduino tutorial.
Audio Out (Part 3) – a PCB design for the discrete buffer circuit is offered this month.