Custom PC, Issue 157

Custom PC Issue 157This month’s Hobby Tech column demonstrates how to use the Raspberry Pi Camera Module to create smooth timelapse footage and reviews the WeMos D1 R2 ESP8266-based Arduino-alike board and Andrew ‘bunnie’ Huang’s Essential Guide to Electronics in Shenzhen.

Looking to the tutorial, this is far from the first time I’ve covered the use of the Raspberry Pi Camera Module add-on. Since its initial launch, however, the software has come on in leaps and bounds including means of finally addressing a longstanding issue with the board: the difficulty in using the timelapse functionality. Where previously you needed a surprisingly complicated script to control the camera, now timelapse capture is handled entirely within the raspistill software. Coupled with avconv – ffmpeg, which I had previously recommended for the task, having been deleted from the Raspbian software repositories – the two packages are all you need to create high-quality timelapse footage directly on any Raspberry Pi.

The WeMos D1 R2 is one of a range of low-cost devices based on the ESP8266 microcontroller and Wi-Fi radio. While getting on in age, the ESP8266 is extremely popular due to its rock-bottom pricing; the only snag being that its form factor makes it difficult to integrate into hobbyist projects. The WeMos D1 R2 aims to fix that by providing a breakout board for the compact ESP8266 in the familiar Arduino Uno layout. While more feature-packed equivalents exist, the WeMos D1 R2 costs just £3.30 in single units – an absolute bargain for an easy-to-use microcontroller with integrated Wi-Fi connectivity.

Finally, The Essential Guide to Electronics in Shenzhen. Kindly loaned by my friend Aaron at hobbyist electronics specialist oomlout, this latest book from noted hacker Andrew ‘bunnie’ Huang is a major departure from the norm. Rather than a how-to guide or white paper analysis, the book is designed to be used as a functional sourcing tool while visiting the Shenzhen area of China complete with maps, point-to-translate pages covering everything from travelling back to your hotel to enquiring as to the tolerance of resistors and capacitors. A pair of prose sections also provide information on doing business in China, including how to spot fake or missold components and how each could affect your project. Niche, perhaps, but a fascinating read – and an invaluable tool for anyone planning a trip to Shenzhen any time soon.

All this, plus the usual raft of interesting things written by people who aren’t me, can be found at your local newsagent, supermarket, or as a string of zeroes and ones on Zinio and other digital distribution services.

Custom PC, Issue 146

Custom PC Issue 146This month’s Hobby Tech column begins with a look at a topic that has been close to my heart for a number of years now: thermal imaging, and how it can be applied to the field of hobbyist electronics and technology review. If that weren’t interesting enough, there’s also a review of the Novena open-hardware all-in-one desktop, and a look at a little-known bug-fix applied to Sinclair’s classic ZX81 microcomputer.

For years, I’ve wanted a thermal camera. Recently, the price of cameras has plummeted and I was finally able to justify – just about – the cost of the entry-level Flir C2. While it takes a while to get used to thinking in resolutions of 80×60 – the total resolution of the Flir Lepton thermal imaging module featured in the C2 – I’ve been having no end of fun capturing thermal data on everything from single-board computers to my cat.

In the column, though, I argue for the application of thermal imaging in the hobbyist realm. With smartphone-connected thermal cameras now available in the low-hundreds, and a broken-out Lepton module the equal of the one found in the C2 available for just £160, a thermal imaging sensor is no longer the preserve of well-heeled professionals. I’ve found mine useful for tasks from finding hot-spots on a board design to spotting heatsinks which were not properly mated to the components below.

When I wasn’t playing with the thermal camera, I was playing with the Kosagi Novena. Born from the mind of noted hacker Andrew ‘Bunnie’ Huang, the Novena is remarkable: it’s a truly open computer, with everything from the firmware through to the board designs being published under an open-source licence. Loaned by UK hobbyist electronics shop oomlout, I was sad to give the crowd-funded Novena back – despite an ARM-based processor outclassed by even the cheapest of x86 laptop parts.

Finally, the ZX81. I’ve been clearing out much of my classic computer collection as I shift to a smaller office, and while I had to get rid of my rather rare Sinclair ZX81 I wanted to record its existence for posterity. From the very original production run, this machine boasted the ‘cockroach’ – a bug-fix for a fault in the ROM implemented in hardware, with a hand-soldered board attached to the top of the system’s CPU. It’s a jarring sight, and one that I was privileged to see in person: only a handful of cockroach-model ZX81s, fixed while the company waited for corrected ROM chips to arrive, exist and they’re all externally identical to non-cockroach models.

All this, plus a wide selection of stuff written by people who aren’t me, is available now from your local newsagent, supermarket, or digitally via Zinio and similar services.