Silicon ChipNet Work - November 2020 SILICON CHIP
  1. Outer Front Cover
  2. Contents
  3. Subscriptions: PE Subscription
  4. Subscriptions: PicoLog Cloud
  5. Back Issues: PICOLOG
  6. Publisher's Letter
  7. Feature: The Fox Report by Barry Fox
  8. Feature: Techno Talk by Mark Nelson
  9. Feature: Net Work by Alan Winstanley
  10. Project: The Christmas Tree that grows! by Tim Blythman
  11. Back Issues: LFSR Random Number Generator Using Logic ICs by Tim Blythman
  12. Project: USB Digital and SPI Interface Board by Tim Blythman
  13. Project: HIGH-POWER 45V/8A VARIABLE LINEAR SUPPLY by Tim Blythman
  14. Feature: P955H PIC Training Circuit by Peter Brunning
  15. Project: Five-way LCD Panel Meter / USB Display by Tim Blythman
  16. Feature: Pedal Power Station! by Julian Edgar
  17. Feature: Make it with Micromite by Phil Boyce
  18. Feature: Circuit Surgery by Ian Bell
  19. Feature: Practically Speaking by Jake Rothman
  20. Feature: Max’s Cool Beans by Max the Magnificent
  21. Feature: AUDIO OUT by Jake Rothman
  22. PCB Order Form: DIRECT BOOK SERVICE
  23. Advertising Index

This is only a preview of the November 2020 issue of Practical Electronics.

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Articles in this series:
  • (November 2020)
  • Techno Talk (December 2020)
  • Techno Talk (January 2021)
  • Techno Talk (February 2021)
  • Techno Talk (March 2021)
  • Techno Talk (April 2021)
  • Techno Talk (May 2021)
  • Techno Talk (June 2021)
  • Techno Talk (July 2021)
  • Techno Talk (August 2021)
  • Techno Talk (September 2021)
  • Techno Talk (October 2021)
  • Techno Talk (November 2021)
  • Techno Talk (December 2021)
  • Communing with nature (January 2022)
  • Should we be worried? (February 2022)
  • How resilient is your lifeline? (March 2022)
  • Go eco, get ethical! (April 2022)
  • From nano to bio (May 2022)
  • Positivity follows the gloom (June 2022)
  • Mixed menu (July 2022)
  • Time for a total rethink? (August 2022)
  • What’s in a name? (September 2022)
  • Forget leaves on the line! (October 2022)
  • Giant Boost for Batteries (December 2022)
  • Raudive Voices Revisited (January 2023)
  • A thousand words (February 2023)
  • It’s handover time (March 2023)
  • AI, Robots, Horticulture and Agriculture (April 2023)
  • Prophecy can be perplexing (May 2023)
  • Technology comes in different shapes and sizes (June 2023)
  • AI and robots – what could possibly go wrong? (July 2023)
  • How long until we’re all out of work? (August 2023)
  • We both have truths, are mine the same as yours? (September 2023)
  • Holy Spheres, Batman! (October 2023)
  • Where’s my pneumatic car? (November 2023)
  • Good grief! (December 2023)
  • Cheeky chiplets (January 2024)
  • Cheeky chiplets (February 2024)
  • The Wibbly-Wobbly World of Quantum (March 2024)
  • Techno Talk - Wait! What? Really? (April 2024)
  • Techno Talk - One step closer to a dystopian abyss? (May 2024)
  • Techno Talk - Program that! (June 2024)
  • Techno Talk (July 2024)
  • Techno Talk - That makes so much sense! (August 2024)
  • Techno Talk - I don’t want to be a Norbert... (September 2024)
  • Techno Talk - Sticking the landing (October 2024)
  • Techno Talk (November 2024)
  • Techno Talk (December 2024)
  • Techno Talk (January 2025)
  • Techno Talk (February 2025)
  • Techno Talk (March 2025)
  • Techno Talk (April 2025)
  • Techno Talk (May 2025)
  • Techno Talk (June 2025)
Net Work Alan Winstanley This month, in an extended issue of Net Work, we look at the vitally important issue of trust in online purchases and reviews. O ne of the core principles of successful sales and marketing is the need to answer a certain question that buyers unconsciously ask themselves before they commit: ‘Why should I trust you?’. That nagging uncertainty and lack of confidence is a barrier to buying, and smart sellers know that they must break down that barrier before achieving a successful sale. Hence the flag-waving claims of ‘Established 50 years’ or ‘Thousands of customers served every day’, perhaps displaying a trade body logo, showing off some illustrated case studies or glowing testimonials. If those claims are true then the product or service must be alright, mustn’t it? Done properly, marketing measures like these dispel doubt and give potential customers the rosy feeling that they are making the right choice. There has of course been a seismic shift in the last 20 years towards the two-dimensional world of online shopping, where it’s second nature to source products and local services. In the UK, the home improvement sector is valued at some £4bn a year, and online trade directories such as RatedPeople.com, CheckaTrade.com and MyBuilder.com have sprung up to steer consumers towards local firms whom they claim are monitored and vetted for quality. Potential buyers pore over details, feedback and reviews, and they check star ratings before engaging a trader. The directories vet their members themselves, though RatedPeople also highlights the government-backed TrustMark quality-assurance scheme (www.trustmark.org.uk) that may apply to some of their traders. Some, more progressive traders, may hold more rigorous SafeContractor accreditation instead. One question worth asking, though, is ‘Who checks the checkers?’ Following consultations and investigations by the UK’s Competitions and Markets Authority (CMA) five years ago, to counter the possibility of fake reviews or the deliberate withholding of negative ones, both CheckaTrade and rival TrustATrader agreed to tighten up their internal review procedures. As far as buying physical goods is concerned, if things don’t work out then EU consumer law (enshrined in the UK’s Consumer Contract Regulations) provides for a 14-day return period, so you could always send stuff back for a refund (including the original basic postage charges), if you don’t mind the hassle of returning them at your expense (unless they are faulty). Remember also that UK PayPal transactions don’t have the same consumer protection that buying directly using one’s own credit card would, especially for items costing over £100. For many online sellers, the problem of cementing ‘trust’ is dealt with by offering star ratings and reviews. We have become conditioned into relying on them before taking the plunge, but how trustworthy are the reviews themselves? Some very underhand tactics can be used to try to garner positive reviews and distort the picture in a seller’s favour. The seeds of doubt Seeds labelled as ‘rings’ and ‘bracelet’ mailed from China to the US as part of a brushing scam. They have not so far proved hazardous. [Image: Washington State Department of Agriculture/Facebook] 12 Earlier this year, people around the world started receiving mysterious little packets of seeds that they knew nothing about. The bags from China were often labelled as ‘beads’ or ‘jewellery’ but contained small bags of seeds instead, causing not a little consternation and alarm to their recipients. As you would expect, rumours soon swirled around on the web: were the seeds a genetically modified biohazard or an act of ‘agro-terrorism’? Did they contain dangerous pathogens? What would happen to the nation’s food chain if they germinated? In Britain, there was even speculation that the seeds might be Japanese knotweed, a destructive bamboo-like plant notorious for undermining foundations and wrecking property! According to the US Dept. of Agriculture (USDA), people from every US state received them, and by the end of August worried citizens had sent some 8,500 packets to the USDA for analysis. So far, though, more than 320 seed varieties have been identified but no biohazard has been found, says the USDA. The puzzling packages have not been limited to seeds, either. Other cheap, unsolicited goods turned up, including flashlights, handwarmers, ping-pong balls and a small keyboard vacuum cleaner that all turned up unannounced, according to America’s Better Business Bureau. What was going on? The packages were deemed part of an ongoing scam that we first saw in Britain two years ago, in which unscrupulous traders (usually third-party Amazon sellers) hijack the IDs of individuals and set up bogus customer accounts using them. The rogue sellers then anonymously mail out low-value goods to the individual’s address, which allows the seller to chalk up the delivery of a ‘successful’ (but bogus) transaction. The scam, called ‘brushing’, then enables phony sellers to post fake positive reviews about themselves, important because as we all know, good reviews create an impression of trustworthiness. Vendors selling through Amazon have been heavily implicated, but other online retailers have been affected too. Beware geeks bearing gifts It is easy enough for Chinese vendors to sell to the West via eBay and Amazon or through portals like AliExpress and Banggood. The level of trade circulating in China is truly enormous: I wrote in 2019 how, on China’s ‘Singles Day’ alone, the volume of trade was Practical Electronics | November | 2020 CH¥ 213.5bn (£24bn, US$30bn), and that’s just on Alibaba. To get an idea of the scale of industry, some YouTube videos offer insights into some Shenzhen-based blocks that are described as the world’s greatest electronics markets. They’re crammed with myriad sales booths, retail counters and more besides, all dedicated to selling gadgetry and electronics technology (see https:// youtu.be/kaKVSANVMRI) Eager to build up credibility and sell their wares to the West, Chinese vendors have taken to offering reviewers free or discounted goods in return for customers submitting a favourable Amazon review. The offer may come in the form of a WhatsApp message or a discrete voucher tucked in with the goods, maybe offering the chance to join a ‘VIP Program’ and tantalising buyers with the offer of more free goods. A whole trade sector has also sprung up that specialises in furnishing their clients with rosy product reviews. Millions of reviews are checked and posted online every week and disreputable sellers may also try to remove poor ones. At the start of the year I sourced a wildlife camera from an Amazon seller in China. It exceeded expectations, but I then received a request to give them a five-star review, along with the offer of a full refund on another model (ie, a free product) subject to a favourable five-star review appearing on Amazon. One Amazon UK reviewer left a scathing two-star review of a China-sourced appliance and then wrote: ‘I [then] received a [personal] email from someone asking me to remove this review or change it to five stars in exchange for a £40 refund in an attempt to raise the rating of their product... I refused the offer and lowered my review from five stars to one star and reported it to Amazon.’ Fake reviews are not a new problem: four years ago the Competitions and Markets Authority shut down an A Google Chromecast dongle that allows media to be cast to the TV through its HDMI port. It also needs a power source. [Photo: author] Internet marketing firm that posted fake reviews to boost their client’s online profile. In an effort to combat dodgy reviews, Amazon UK recently took down no less than 20,000 of them, written mostly by a handful of Amazon’s ‘top reviewers’. One contributor submitted a five-Star Amazon review of various Chinese products every four hours on average. The Financial Times newspaper then revealed that he had resold many of the goods on eBay. The reviewer denied any wrong-doing and claimed they were duplicate, unopened goods. Amazon states it has 8,000 staff processing reviews and rigorously takes steps to prevent feedback from being manipulated. Not so starstruck Most traders are honest though, and some vendors on Amazon now face an even bigger problem: fake one-star reviews that are posted onto their product pages by dishonest rivals in order to derail their business. It doesn’t take much to scare off an unsure buyer and a handful of one-star reviews can sink a legitimate business almost overnight. ‘Business fell off a cliff’, said one such maligned seller who gave it all up as a bad job. eBay sellers have similar issues when chasing down malicious Detailed Seller Ratings (DSRs) intended to harm their sales. Over time, one learns to take reviews and feedback with a pinch of salt. One excitable reviewer on Amazon left nothing but five stars for every purchase, possibly to convince herself about her decision to buy them in the first place. Recently, several Amazon customers had problems with facemasks not arriving from a European seller: after complaining directly to the seller, they posted five-star reviews just because the vendor promised (hurrah!) to send some more. We’ll never know if they arrived because the seller’s account got shut down by Amazon. Five stars too for some photo paper: ‘I haven’t used it yet but since Epson quality is reliable I imagine it will be just as good as it was last time. No complaints at all.’ A four-star review for spraypaint said ‘Seems good, but I have not used it yet,’ while another one marked down an electric fan to one star, stating ‘Fan no good because it only blows air around, it does not cool it down.’ A helpful five-star review too for a Christmas gift: ‘Cannot review as not used yet, bought as stocking filler for Xmas.’ The comedy goes on. Before buying, probably the best tactic is to check the most recent seller feedback and look for suspicious patterns such as a flurry of five-star (or one-star) reviews all dated roughly the same time. With experience, and maybe after suffering the odd setback, online buyers are learning to become much more sophisticated and discerning when shopping online. A king’s ransom Floor to ceiling electronics: a look inside ShenZhen Huaqiangbei Electronics Market (Image: Nikolay Tanev / YouTube) Practical Electronics | November | 2020 Last month, I highlighted how ransomware had hit Blackbaud, a popular services provider that hosts web services on behalf of many institutions 13 NVidia’s Shield TV is a powerful Androidbased digital media player for demanding users and gamers. It has Wi-Fi and Ethernet, and works with Alexa and Google Assistant. around the world. Blackbaud joins an increasing number of victims that decided to pay the ransom. For their 2020 report, The State of Ransomware, security specialist Sophos commissioned an independent survey of 5,000 IT managers in 26 countries and the results were quite surprising. They found that 51% of respondents had been hit by ransomware in the last year, but increasingly the main targets of the ‘smart’ criminals were now server-based systems rather than small operators. Of those affected by ransomware since 2019, over 70% of respondents had at least some data encrypted but 94% managed to get their data restored. Big business has insurance covering such losses but, interestingly, Sophos found that it was ultimately twice as expensive to pay a ransom instead of restoring systems from backups and dealing with the fall-out. In Spain, just 4% paid the ransom and 72% restored from backups, but in India 84% of respondents had been hit and 66% of them paid the ransom. Overall, just 1% who paid a ransom did not get their data back – maybe a sign of ‘honourable thieves’ finding that they can rake it in by offering a ‘professional’ service. (Download the 2020 report from Sophos at: http://bit.ly/pe-nov20-sophos) Tune into Android TV The way we access TV entertainment is changing, thanks to Internet access, smart apps, streaming services and Freeview ‘Play’ TV. Home network users who enjoy the likes of Netflix, YouTube, Amazon Prime or catch-up 14 TV will know that an ordinary ‘dumb’ HDMI TV can access streaming content by adding a powered HDMI Wi-Fi dongle. Amazon offers a remote-control Alexa-powered Fire TV Stick 4K UHD (£50), and smartphone apps and voice controls make it easy to queue up content for casting onto the TV. Google offers their Google Chromecast dongle (£30) or 4K Chromecast Ultra (£69) and Android apps are great for queuing up and casting YouTube content from a phone or tablet onto the big screen. These HDMI dongles can give older TVs another lease of life. Whether to buy into Google Nest or Amazon’s Fire depends on how deeply you are wedded to either eco-system. I have three Google Home Minis (the second generation is called Nest Mini) dotted around because I frequently google for answers, definitions, reminders, the time or the news. A Google Nest Hub on my desk handles voice search and displays ‘written results’ on its LCD screen: it’s a great desktop tool for a busy internet worker. I have just one Amazon Echo Dot to ask ‘where’s my stuff?’, though ‘skills’ can be added to interface with many IoT devices or automate other tasks (the same being true of Google Nest apps). Of the two systems, Amazon’s offer is probably more family friendly all round and I sense that it slightly has the edge. Frequent googlers (or those who use, for example, Google Calendar) will prefer to use Nest, which is configured by the Google Home app. Add-on HDMI dongles like Chromecast also give you a fighting chance of ‘outsmarting’ troublesome smart TV apps by using smartphone apps instead. For example, the author discovered his ageing Samsung smart TV simply refused to run the My5 ‘catch up’ TV app anymore: the TV just locked up. The My5 app for Android ran perfectly on a smartphone and enabled Channel 5 programmes to be cast to the Chromecast dongle instead. There was no reply from Channel 5 when I pointed this out. Google is releasing a new HDMI dongle probably called Google Chromecast with Google TV. The fully-fledged Android TV device has a remote control and incorporates the usual streaming apps along with a D-pad, buttons for YouTube, Netflix and support for Google Assistant and Google Play apps and games. It’s expected that ‘unlisted’ Android apps can also be sideloaded onto the dongle. Release dates, prices and technical specs are sketchy, but it’s worth watching out for as a way of adding extra Android functionality to an HDMI TV. Other streaming media players include the Xiaomi Mi TV Stick (£35, scan.co.uk) which runs Android 9.0 and its basic remote control has buttons for Google Assistant, Netflix and Amazon Prime; devices from Roku start at £30 and rumours circulate of a forthcoming Nokia-branded Android TV dongle as well. For network-hungry users or gamers, there’s the NVidia Shield, a powerful Android TV media streaming and gaming device that works with Alexa and Google Assistant and has Chromecast 4K built in, along with 2.4/5GHz Wi-Fi and gigabit Ethernet. It offers HDto-4K upscaling using AI. Prices start at a penny under £150.00. Full specs and details of the pricier Pro version are at: www.nvidia.com/en-gb/shield/ Other news The speech recognition and context-awareness skills of Alexa and Google Assistant are extraordinary, but did you know that all your speech queries and clips are memorised in their systems? To review your Alexa voice commands, open the Amazon Alexa app on your smartphone and go More/Settings/Alexa Privacy. There you can review Voice History and delete any recordings from memory. You can also enable ‘Deletion by voice’ and Alexa will erase recordings on command. Instructions to delete Google Assistant recordings are at: http:// bit.ly/pe-nov20-google Chinese video clip giant TikTok, which like Huawei has come under fire from the US Government, has announced its first European data centre will be built in Ireland at a cost of about € 420 million. TikTok is also rumoured to be considering building its HQ in London, but perhaps the outcome of stormy UK/EU Brexit negotiations, due to conclude in mid October, may cause a re-think. TikTok was threatened with an outright ban in the US due to fears of personal data being exfiltrated to mainland China. In September, the US approved an effective takeover of Tik Tok’s US operation by Oracle and Walmart. The status of current Huawei smartphones is now becoming less clear, despite earlier assurances that existing Huawei devices would continue to receive Google updates. The author’s Huawei continues to update, but extended US licences that permitted Google to keep apps refreshed expired in early August. The US has also choked off supplies of semiconductors to Huawei and is considering sanctioning other foundries too. Huawei is far from finished; it has developed its own OS called Harmony and is rapidly building up its own library of apps including signing Practical Electronics | November | 2020 up TomTom. Meantime, the US faces a bill of some $1.8bn to rip out and replace telecoms equipment that ‘poses a national security threat’ – mainly, hardware made by China’s ZTE and Huawei. Ironically, America, in turn, has had its own data protection standard (Privacy Shield, formerly Safe Harbor) invalidated by the EU. This follows a legal case dubbed ‘Schrems II’ (see Net Work, August 2018 for background) which ruled that America’s own privacy controls still failed to adequately safeguard EU data subjects from US surveillance. As a result, many readers will have seen emails from Facebook, Google and others concerning the use of so-called SCCs instead – Standard Contractual Clauses cover the transfers of personal data out of the Europe Economic Area, Switzerland and the UK. The use of SCCs has been allowed by the EU for the time being, but further negotiations will have to be hammered out with neither side showing signs of giving way. Disappointment for those awaiting the launch of the new Intellivision Amico TV games console (Net Work, August 2020). Disruption caused by Covid-19 has resulted in the postponement of the launch until April 2021. Proposals made four years ago by Facebook and Google to build a new undersea cable between the US and Hong Kong have been banned by US authorities, due to ongoing security concerns. Revised plans for a cable connecting the Philippines and Taiwan instead have been re-submitted. ...and in space In early September, SpaceX successfully launched its twelfth Starlink mission, lobbing another 60 Starlink America’s Privacy Shield data standard (formerly Safe satellites into LEO (low Harbor) has been invalidated by the EU over privacy and earth orbit), making surveillance concerns. Standard Contractual Clauses roughly 650 to date. (SCCs) are being implemented in its place. The mission’s first stage landed for a low-cost connectivity for IoT devices second time on the SpaceX drone ship, in agriculture, marine and more. You Of Course I still Love You. can track the SpaceBEE coverage at: Swarm Technologies successful- https://swarm.space/leo-labs-globe/. ly launched their first 12 SpaceBEE That’s all for this month’s roundup – microsatellites on 2 September (Net see you next month for more Net Work! Work, Oct 2020). A total of 150 of the The author can be reached at: 400 gram saucer-sized SpaceBEEs are alan<at>epemag.net destined to circle the earth and offer ESR Electronic Components Ltd All of our stock is RoHS compliant and CE approved. Visit our well stocked shop for all of your requirements or order on-line. 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