Net Work February 2024

This month’s column proves how power supply glitches can catch out even seasoned home network users, suggests some cheap and cheerful workshop tools available direct from China, and there’s a quick roundup of space news as well. Here’s a summary of this month’s feature.

A NASty surprise

^ My Synology NAS suffered a hard disk failure due to constant power supply interruptions, hence the yellow LED. A small UPS from Power Inspired was fitted afterwards to safeguard against future outages.

^ An iPower-DC2 multi voltage UPS in use powering several items on my network

I’ve been trialling a 12V mains adaptor-style UPS and a multi-voltage compact type on my home office network, as shown in Net Work, December 2023.  Then, just a few days before I penned this month’s column, the mains electricity supply failed at midnight without warning. The ‘juice’ was then restored before flashing on and off again at least half a dozen times over the following half hour. Happily, the 9V and 12V UPS supplies powered the modem and router without complaint, but a flashing amber LED and beep on the NAS warned of a ‘degraded volume’ . The repeated power cycling had corrupted a hard drive or maybe crashed it completely.

^ This handy checker tests the polarity and presence of a DC supply – handy when working up a ladder installing CCTV, or under a bench installing new gear.

Error messages confirmed that one 1TB disk was down, although its condition was described as ‘healthy’ and the other disk was spinning as normal. There were options to ‘repair’ the damaged data but they advised replacing the degraded drive, which is what I did. A welcome touch was Synology’s ‘Locate disk’ feature that flashed the dodgy disk’s LED to make sure the correct drive is swapped out, guided by their commendably clear online instructions. I again chose Western Digital’s ‘Red’ NAS drives, but the minimum capacity I could find was 2TB, meaning I needed to upgrade both disks at a cost of £175. This just goes to show that power outages can hit anybody – the rigmarole was an expensive and time-consuming problem to sort out.

Readers might be interested in the UPS manufacturer’s data sheet at https://www.powerinspired.com/brochures/br-ups-dc2.pdf and a block schematic of the UPS with some very interesting design notes is at https://www.powerinspired.com/product-range/ipower-dc-ups/ipower-dc2-dc-ups-functional-description/. Note that previously-published URLs linking to these products have since been updated by the manufacturer.

Spoilt for choice

These days, many readers source products directly from China and the range of merchandise sold by the likes of AliExpress and Temu is dizzying. One thing that’s undeniable is the tempting pricing, and a discerning hobbyist who knows what he’s looking for, and doesn’t mind a little bit of a gamble, can often bag a bargain. It seems as if AliExpress and Temu are slugging it out for trade, and I discovered that, if you can accept a few oddities or rough edges here or there, AliExpress offers some interesting-looking and unusual tools and equipment at almost silly, giveaway prices that will help constructors to get more out of their hobby. Here are a few that caught my eye.

^ The Yihua 929-D is a 30W desoldering iron and suction pump, costing just £10. EU and US voltages available. (AliExpress)

^ A ‘plastic welder’ uses hot staples to melt and stitch ‘unglue-able’ plastic panels and parts back together again. It could easily pay for itself after one job. (AliExpress)

^ This complete wire ferrule crimping kit includes a lifetime’s worth of ferrules for under £10. (AliExpress)

 As constructors doubtless know, when stripping the ends from multistranded wire, stray copper whiskers can be a menace as they can short to neighbouring terminals or the chassis. Wire ferrules are used to dress the ends of such wires neatly, and I noticed AliExpress lists a complete ferrule crimping kit including 1,200 ferrules for just £5.61 plus shipping and tax. Search for ‘Crimping Pliers HSC8 6-4A Tubular Terminal Crimper’.  Ratchet-type tools are sold for car-type blade crimp terminals, eg ‘SN Series Crimping Pliers SN-48BS’ for just £7.39 + taxes etc. At these sort of prices, not many will mind adding them to an order to make up a postage-free order value, as they might come in useful one day.

A lot of hot air

^ The popular 858D hot air reworking tool is designed for working with surface-mount devices or heatshrinking, amongst other applications. (AliExpress)

With the advent of surface-mount devices and the need to service eg smartphones or laptops etc, another useful soldering tool for a busy workbench is a hot air reworking tool. These can simultaneously melt larger areas of surface mount joints to enable BGA chips or components to be replaced. For hobbyist users, the popular ‘858D’ type is ridiculously cheap on AliExpress, and many clones are available from £22 + tax. The temperature and fan speed are variable and different size nozzles can be fitted. Some models include a soldering iron, and spare exhaust fans and handles can be had for pocket money prices.

^ A very compact but powerful spot welder is used for making up battery packs using nickel strip. This model has an OLED display. Tinted welding safety spectacles are absolutely essential.

If the idea of making your own battery packs appeals, then small but powerful welders are sold that will spot-weld nickel strips into place on, say, 18650-type rechargeable cells. Small units start at about £20 and I sourced a compact handheld one with an OLED display, for under £40. They are USB rechargeable and produce quite an alarming kick that belies their small size. Strangely, the term ‘gear’ is commonly used to describe power levels; ‘gear adjustment’ can offer, say, ‘30 gears’ of energy. The necessary nickel strip for welding connections together is sold separately in various gauges.

These devices are emphatically not for casual workers or the faint-hearted and, because of the variables involved, individual spot-welds can sometimes be hit or miss. Without exception, extreme care must be taken to safeguard against glare or “welder’s arc eye” – I speak from experience after administering first aid (special eyedrops) to save a welder’s eyesight in years gone by. As these devices sometimes belch out a big, fat spark, metal spatter is another hazard: it will damage plastic spectacle lenses as well as your eyesight, so suitable welding-grade tinted safety spectacles or googles have to be worn. I noticed that some models now have a foot pedal control too, which is a good idea.

If you’re looking to add to your workshop toolkit, plenty of choice is available at budget prices but when ordering, keep an eye out for added sales tax and postage costs, remembering that delivery can sometimes take many weeks. You can sign up for an account at aliexpress.com.

Artificial influencers

^ No-brainer: Aitana Lopez is an entirely AI- and Photoshop-generated ‘influencer’ who has gained more than 120,000 ‘followers’.

A Spanish agency called ‘The Clueless’ has created a sassy AI/ Photoshopped  ‘influencer’ character called Aitana Lopez who, according to Euronews at (probably NSFW)  http://tinyurl.com/44phc7m4, has garnered over 120,000 Instagram followers. She has even been asked out for a date by an unknowing admirer. Aitana earns the agency upwards of €3,000 a month as a ‘presenter’ and such is her success that a second AI star called Maia Lima is now on the payroll as well. You can see Aitana’s portfolio (NSFW) at https://www.theclueless.ai/project/aitana-lopez.

Space News

Regular readers will recall the sad demise of Virgin Orbit’s ambitions to offer a 747-based satellite launching service that would have flown from an ordinary runway instead of needing a vertical launchpad. A make-or-break flight of the ‘Cosmic Girl’ 747 from Cornwall in England last year failed to deploy its payload and the company subsequently collapsed. Cosmic Girl lives on, however – the aircraft has now been acquired by Stratolaunch, a Californian-based air launch company, where she is now known as ‘Spirit of Mojave’. (If you use  flightradar24.com, the 747’s registration is N744VG.)

^ The Stratolaunch ‘Roc’ is the world’s largest aircraft, and will air-launch payloads including hypersonic craft. (Image: Stratolaunch)

The firm is also developing the world’s largest aircraft, a twin-fuselage six-engine ‘Roc’ launcher vehicle originally intended to launch customer payloads into space, but there are now major ambitions to launch hypersonic vehicles as well. Incidentally, the port-side cockpit is a dummy and is known as the ‘mockpit’. More details at www.stratolaunch.com.

The first commercial runway-landing spaceplane to be built by the private sector is now complete and is soon to undergo trials at NASA. The Dream Chaser space vehicle (see Net Work, August 2023) is named ‘Tenacity’ and has been built by Sierra Space to provide at least seven flights to the international space station. You can learn more at https://www.sierraspace.com/dream-chaser-spaceplane/

^ The Dream Chaser spaceplane ‘Tenacity’ is undergoing testing with NASA and is destined to service the international space station.

Returning to last month’s Ecowitt weather station topic, out of interest I tested a wire-ended WN30 temperature probe on a deep freezer last month and the screenshot of the mobile app shows how it fell from +19.4°C to -18°C and then clearly recorded the cycling of the fridge compressor (and me opening the door). Data is also uploaded to the Ecowitt cloud server. I was pretty impressed by the performance and data it captured.

^ Screenshot of the temperature data captured by an Ecowitt WN30 wire-ended probe, tested on a deep freezer.

Finally this month, while surfing around I stumbled across a USB dongle with a difference: far from being a benign flash drive, it contains a voltage doubler circuit and a bank of capacitors that are designed to test (and/ or destroy) a USB host by injecting high ‘killer’ voltages onto the data bus. You can see it in action at https://www.youtube.com/watch?v=I6bRoSK39io.  Some bad actors are fabricating similar devices themselves, which is one more reason not to plug untrusted dongles into your hardware.

That’s all for this month’s Net Work summary. You can read full details in my Net work column in this month’s Practical Electronics magazine.