Net Work July 2024

This month’s magazine column has more useful ideas for USB charging and monitoring plus practical advice about hobby and craft adhesives found online, as used in precision smartphone repairs. There’s more space programme news as well. Here’s a summary of what’s in store.

In last month’s column I showcased some USB-powered products that typically use a 5V USB source to recharge their internal batteries. Whether it’s a camping light, earbuds, Bluetooth speaker or a powerbank, it seems that almost every Chinese-made gadget or rechargeable device now arrives with a USB-C lead included for use with your own charger. A ‘hanked’ lead is one formed by coiling it between two spindles or around a bar to produce a tidy coil, usually with a wire tie twisted round the middle or retained with a fancy sleeve. Apple addressed the thorny problem of producing hanked USB leads many years ago, by shaping them around two mandrels as shown in Apple’s patent, downloadable from the US Patent Office at https://ppubs.uspto.gov/dirsearch-public/print/downloadPdf/9073727.

Silicone cable ties and clips (pictured above) are available cheaply from Temu, and are quite handy for keeping USB leads manageable. (While I was at it, with online security in mind, I spotted some stick-on privacy covers for my laptop’s webcam that work perfectly.)

^ The KOWSi KWS-065C is a thumb-size inline USB-C monitor showing voltage, current, wattage, capacity and elapsed time, and is rated up to 6.5A.

The latest ‘rounded-rectangle’ USB-C connector is now commonplace and, as I showed last month, things get more interesting when ‘Power Delivery’ (PD) is involved. Since last month, several more USB leads and monitors have arrived from China which I’ve been testing over the past few weeks. The KOWSi KWS-065C is a useful thumb-size inline device showing voltage, current, wattage, capacity and elapsed time. The similar KOWSi KWS-066C crams more data on a colour display and shows temperature as well.

^ The KOWSi KWS-2301C offers a 0.77” OLED readout showing five lines of data, including direction of charging. It is rated up to 12A and will be very useful for monitoring high-power charging.

Another KOWSi USB-C monitor, the KWS-2301C, has a 0.77” HD mono OLED readout that nearly blew me away: although more compact in size, its comprehensive display shows five lines of data including time, maximum values, CPU temperature and direction of flow.

Untangled cables

^ This braided USB-C lead by Essager has a built-in digital display for power and PD, and is tangle-free. It’s rated at 100W, 7A.

Higher-power USB charging cables are available that have a digital display built into a USB-C plug for convenience, and I managed to source a braided 1-metre long USB-C lead sold under the Essager brand. Just like the tiny inline USB-C monitors described last month, it displays the wattage and PD (when available) on a small seven-segment display, which will be adequate enough for keeping an eye on a device’s charging status. I liked the flexible and tangle-free braided sleeving and the cable is rated by the makers at up to 100W, 7A. It could also be handy when charging all sorts of small appliances that use a USB-C charger. It’s now my go-to favourite for USB-C charging.

^ UGREEN offers quality braided charger cables of various lengths that are flexible and easy to manage. A right-angle braided USB lead offers a more compact connection that is less prone to accidental damage.

I also sampled some UGREEN brand braided cables that are 0.5m long, with A-type plugs at one end that will fit in my desktop USB charger. Again the flexible ‘memory free’ cable sleeving helps to keep them tangle-free and twin packs are sold by Amazon. To help avoid accidentally causing damage to the charging port of, say, a smartphone or tablet, it might be worth considering using a right-angle USB lead which doesn’t protrude so much. I found a short 0.5M braided type made by UGREEN on Amazon.

Powerbanks themselves are widely available and USB-C charging ports can be bidirectional: they can recharge the powerbank as well as charging a device. It’s easy to overlook this so it’s worth double-checking the user manual to make sure. The KOWSi KWS-2301C mentioned earlier, clearly shows the direction of current flowing in a bidirectional connection.

^ For experimenters, low-cost ‘PD trigger’ modules or ‘decoy boards’ can trick a PD power source to create a variable voltage DC supply for your projects. A dip-switch type is also shown.

Electronics experimenters might be interested in some low-cost ‘PD trigger’ modules that are sold online. Also called ‘decoy boards’, they are designed to ‘trick’ a USB-C PD supply into outputting a higher voltage, for use as a DC power supply. Some use a dip switch to select the voltage while others work at a fixed voltage (9V through to 20V). User reviews are mixed, but the low cost makes it worth experimenting with them. AliExpress offer a variety of cheap ones and Amazon has one with dip switches, code B0BGPH1675 (illustrated).

Finally on this topic, with the forthcoming holiday season and air travel in mind, it’s worth remembering that there are strict regulations regarding the carrying of lithium batteries, spare batteries and lithium-ion powered devices (which includes laptops, powerbanks, e-cigarettes and ‘smart’ luggage tags) on aircraft. The IATA rules regarding what should be ‘carried on’ and what cannot be stored in ‘checked-in’ baggage can be found on the IATA website, and a PDF is available at https://www.iata.org/contentassets/6fea26dd84d24b26a7a1fd5788561d6e/passenger-lithium-battery.pdf . It will be worth double-checking with your airline before travel, and general dangerous goods guidance is published by IATA at https://www.iata.org/en/programs/cargo/dgr/dgr-guidance-passengers/

Behind B-7000

^ Handy tools designed for prying open and disassembling electronic products are widely available online. A small 15ml tube of B-7000 adhesive is also shown. Smaller 3ml ones are sold as well.

Also this month I look at some DIY maintenance tools and service aids that will enable techie enthusiasts to carry out some mobile phone repairs, including (in my case) replacing the earpiece of my Huawei smartphone. I’d never heard of ‘B-7000’ until now and a 15ml tube of this mystery glue duly arrived via eBay. It turned out to be a clear, self-levelling acrylic adhesive, dispensed via a needle-point nozzle with a low viscosity that allowed an accurate bead of glue to be drawn – you need a steady hand – around the edge of the phone.  I talk about various adhesive options and viscosity as well.

Other glues have different viscosities and hardness, and some are also offered in black (eg T-7000). After trying the glue, I’ll keep a tube or two of B-7000 in the workshop for delicate repairs, and a comparison of properties is published at https://www.zhanlidaadhesive.com/which-to-buy/?v=920f83e594a1. The product is on the usual websites and it will pay to shop around. You canbuy small 3ml sizes too, and I suspect it is one of those products that is subject to ‘cloning’.

• Readers interested in maintaining quartz watches, batteries and straps might find the author’s Watch Battery DIY Handbook useful. It’s A4 size and contains many worked examples and close-up colour photos of actual tasks, coin cell data and more, and is available on Amazon, B0CPBVG3K6.

Other news

^ A sample of Martian soil deposited into a small titanium tube by NASA’s Perseverance rover, awaiting collection and return to Earth some time into the future. (Image: NASA)

At the time of writing, we awaited news of Boeing’s new crewed Starliner being launched by an Atlas rocket. The launch had been postponed due to an oxygen relief valve problem. In Net Work, August 2023 I reported on NASA’s grand plan for the Mars Sample Return (MSR) project, an extremely ambitious project to bring back to Earth soil samples that have been drilled by NASA’s Perseverance Rover. Some two dozen samples from various locations have been collected (all methodically logged at https://science.nasa.gov/mission/mars-2020-perseverance/mars-rock-samples) and sealed in tubes ready for future collection. You can see the principle being tested at https://youtu.be/WLFyuRswVYA . Perhaps one day into the future, long after Net Work has evolved, samples from Mars will finally be returned to Earth for the first time.

Steep tariffs placed on Chinese EVs in America have kept them off the US market, so shiploads of them are apparently destined for Europe instead. Sources claim that more Chinese EVs cars are being produced than can possibly be sold, and new, unsold ones are stacking up and disrupting European ports. (An interesting analysis is in a blog entry at https://cleantechnica.com/2024/04/11/unsold-chinese-evs-are-piling-up-at-european-ports.)  As for the problem of scrapping old EVs, I’ll close this month with a link to a Bloomberg news item which shows unwanted, obsolete EVs piling up and rotting away in China: you can see more at https://www.bloomberg.com/features/2023-china-ev-graveyards/

Also see https://www.youtube.com/watch?v=1SEfwoqKRU8

That’s all from Net Work for the time being.