February 2022

Arduino-based Adjustable Power Supply

Ideal for powering smaller projects, this design centres around an Arduino to form a compact variable power supply capable of delivering up to 14V at 1A. The PSU is effectively an Arduino ‘shield’ that plugs directly onto an Arduino  Uno. It’s complete with a control program that runs on a PC or laptop to provide a digital dashboard, offering hobbyists with up to five programmable ‘presets’. Just the thing for saving space on a busy benchtop.

Battery Monitor Logger

Knowing the condition of batteries in equipment is essential for keeping them healthy and serviceable. A system that can monitor and, more importantly, log vital battery usage data is likely to be a great aid and it can help you to anticipate or troubleshoot potential problems with battery supplies ranging from 6-100V, monitoring up to three loads separately.  The project utilises a Micromite LCD Backpack to provide a colour touchscreen controller and data is available on-screen or as a .csv file. PIC microcontroller codes can be downloaded via our library.

Electronic Wind Chimes (Part 1)

This electronic version of a wind chime relies on solenoid strikers to produce a tuneful effect on an array of up to 12 chime tubes. No wind required! It provides for sequence recording and playback and configurable randomness, along with that all-important auto silencing at night time. Circuitry and construction are described this month, and testing, adjusting and setting up details will be provided in Part 2 next month.

Mini Digital AC Panel Meters

In this follow-up article on using low-cost, off the shelf digital panel meters, we look at meters designed for measuring AC voltages and currents. Some modules have extra features including power, energy consumption and frequency as well. We give you an idea of how they work and how to apply them in your projects.

KickStart
Part 7: Plug and play with I²C

This instalment fast-tracks readers into making use of I²C interfacing, using an example of an FM radio using I²C to control both the TEA5767-based radio module and an OLED display.

Max’s Cool Beans

More of Max’s multi-colour musings about wireless LEDs and special effects, such as those on YouTube here.

Also in this issue:

• Techno Talk – supply problems that the semiconductor shortage are storing up
• Net Work – looking at Ryobi’s OnePlus 18V power tool system, adding Bluetooth to audio equipment and more news on nuclear power generation and space programs
• Flowcode Graphical Programming (Part 2): RedBoard and PICs.
• Audio Out: Analogue Vocoder (Part 4): Driver Amplifier for our DIY Vocoder
• Circuit Surgery: our in-house surgeon offers an in-depth analysis of op.amp offsets.
• Make it with Micromite: Part 33: using CRC with iButtons and the Micromite

In next month’s issue:

Mini Isolated Serial Link; the Geekcreit LCR-T4 Mini digital Multi-tester; Electronic Wind Chimes (Part 2); Battery Monitor Logger (Part 2);  Contents may be subject to change.