Category - Computers & Tech

Christmas Presents I – Drones

18/11/2020

I just had to get me one of these!

I’ve been fascinated by drones for years, and always had plans to get one. They’re a tad expensive, I admit, but I saw that DJI were just about to release the Mini 2, and I thought it would be an ideal opportunity to get in on the ground floor. So I ordered the Fly More Combo pack through Amazon, and it came next day.

The Mini 2 weighs just under 250g. When you fold out the four propeller arms and remove the gimbal (camera) cover, you’re ready to take off. Well, you are once you’ve set everything else up – which isn’t difficult at all.

The kit comes with a remote control unit, and you need a smartphone to use it. You have to download the DJI Fly app and run through the setup process, which only takes a few minutes, but then you’re good to go.

I wanted to be within the Law, so I went to the Civil Aviation Authority (CAA) website and passed the necessary test to become an approved drone pilot (it’s free). That gave me my pilot/flyer number, which I’ve stuck on the side of my drone. It’s valid for three years. Technically, I didn’t need to do this for the Mini 2 as it weighs less than 250g – but only just, so I thought I may as well in case I upgrade at any point (in any case, the sticker I put on it with my flyer ID has probably taken it to 250-251g). It only took about 15 minutes of revision to pick up some of the numbers about how close to people and buildings you should be, and that was that.

The Mini 2 records at up to 4K video, so it is broadcast quality. You can alter the video quality down to HD, and change the frame rate, but 4K can record at up to 30fps. In HD, it goes up to 60fps. It doesn’t record automatically the moment you turn it on, and you select the function through the app as you’re controlling the drone. This is a sample of what I recorded recently, showing the three levels of zoom available at 4K.

And this is an example of a slow pan at around 80m altitude.

Incidentally, I was terrified of how well I’d be able to control it, so I made sure I was in a big field with nothing I might hit anywhere near me.

The Fly Combo kit comes with three batteries, and each will give about 30 minutes of flying time. You also get a spare set of propellers (4 x 2) and screwdriver to replace them with. A spare set of propellers (if you needed one) currently costs £11 from DJI, so no big problem. The thing is, they are very fragile, and if you were to let them hit anything then they could easily shatter. I think they’re made from carbon fibre, but they are very light.

Control is smooth and easy. You’re not going to fly into things unless you’re a total klutz. You can buy propeller protectors if you’re worried, anyway. When hovering, it is rock-steady up to Beaufort Scale 5 (fresh breeze). You can also get a 1-2 year accidental damage warranty, which is offered when you sign up to the app during registration – and I recommend doing it, just in case. It isn’t expensive.

The Mini 2 has a range of 4km (4,000m), but you should never let a drone out of your sight, and in the UK you’re limited to 120m (400 feet) altitude and how close you can get to people.

If you’re buying someone a Christmas present – and if you’re going to splurge, as opposed to buying them socks or deodorant – this is the way to go! It is brilliant fun, with the bonus of superb quality video.

As I say, these samples were taken in a field not too close to buildings when I was out testing it just after I got it. It’s a great experience flying it around, seeing it ascend and descend, and race around a large open space. But it is also good for stable stuff – checking the pointing on chimney stacks, for example. Once we’re out of COVID, I’ve got lots of plans for where I want to fly it.

I should point out that DJI drones are probably the best you can get (certainly one of the best), but there is a plethora of cheaper drones that are ideal for kids or those on a smaller budget.

Ring 3 Plus Doorbell And Chime Pro

21/10/2020

DOAADI

Computers & Tech

Update: As a result of fairly frequent issues with the Ring not recording video, recording blank video, or dropping off the network altogether (requiring troubleshooting and rebooting) – which has caused me to miss several callers and deliveries – the final straw came with Ring’s discontinuation of the desktop app. I have switched to the Reolink PoE Doorbell as of mid-2023.

During the lockdown, I took the plunge and bought a Ring 3 Plus video doorbell. After unboxing, setting it up was easy, and it connected to my home network with no problems.

After I’d hardwired it in and located it outside the front door, it was working fine. The only thing niggling me was the fact that since the distance between my router and the doorbell was about as much as it could be, and went through every wall and floor possible, the doorbell signal showed up as ‘poor’ on the Ring app. I don’t like things like that and had plans to resolve it later.

Then, once I knew the doorbell worked as it should, I bought a Chime Pro (2nd Generation). This contains a network extender, and once set up you have the option to switch your doorbell to the ‘Chime network’, for which the Chime Pro is effectively the hub.

The Chime Pro has only one button – a reset – and is a small box which plugs directly into a mains socket. In theory, you plug it in, connect it via the app, and you’re done. But it is the most God-awfully difficult thing to get to connect. I managed it eventually (actually, twice eventually, as you will see), though I have no idea what I did to get it to do so.

Now, when the doorbell is connected to the Chime Pro network, it has a ‘good’ signal. But the Chime Pro is also downstairs, and it still has to connect to the home network upstairs. And although it has fewer walls and floors to get through, the signal to my main router was still showing as somewhere between ‘OK’ and ‘poor’. My plans to resolve the issue now came into play.

I next purchased a TP-Link AC2600 range extender. That was a bit of a pfaff to get going, but following a YouTube video from TP-Link – which fully contradicted the idiotic ‘expert’ reviews on Amazon – it worked first time just by pushing the WPS button on the extender and my router. In hindsight, I suppose it was actually very easy to set up – but only if you watched the video, since the instructions that come with it are useless. But now the fun started – and bear in mind that the doorbell and Chime Pro were working flawlessly other than for the signal strength up until this point.

The first obstacle came when I realised that the TP-Link extender puts out its own SSID, and so is effectively a completely separate network. Two networks, actually, since it has a separate SSID for 2.4GHz and 5GHz. I spoke with Ring technical support to ask about changing to a new network. To be fair to them, they try to be extremely helpful, but – like many tech support lines (and I used to work in one, remember) – the people staffing them don’t necessarily fully understand what you are asking them, and don’t necessarily fully understand what they are trying to tell you. Consequently, I opted to simply delete everything I had previously set up, and start all over again.

After removing all registered devices from the app, I started the set up process for the doorbell again. I hit a brick wall straight away, since the app asks you either to scan a QR code or enter a 5-digit number printed below the QR code for your doorbell. And where is this code? It’s on the back plate of the doorbell case – which in my situation was screwed against the brick wall of my porch!

Lesson #1: When you set up any Ring device (they all have these identity codes), write the 5-digit number down somewhere and keep it safe before you try to install anything.

Anyway, whereas the first time I set it up simply chose my home network, this time I had two others to decide between – the 2.4GHz and 5GHz signals coming from the extender. I had noted that when I installed the doorbell the first time, it had automatically connected to my home network’s 2.4GHz channel, so that was the one I chose here – but this time, the one coming from the extender. It ran through the app process and connected first time.

This was where the fun started again. I now came to install the Chime Pro, and – just like before – it didn’t want to. I’ll cut a long story short, and point out that when I chose the 5GHz channel on the extender instead of the 2.4GHz one I’d been playing with, it connected. I’m not sure if it connected first time, but it connected.

At this stage, everything seemed to be working. Signal strength was now ‘good’ for both devices. However, later on when I switched to ‘live view’ on my PC – trust me, if you get one of these things you’ll keep playing with it to start with – I got a blank screen. I tried a few more times and live view appeared. But over the next few hours it was intermittent between a blank screen, a normal image, and a variably grainy one. That persisted into today. Obviously, something was still not right.

I should point out that the doorbell and Chime Pro were still working, and I was getting notifications when someone came to the door or if they pressed the bell (why do people knock when you’ve got a bloody bell?) Video was being recorded and saved. It was just live view that was playing up.

During the day, I was looking for possible issues reported by others on the internet. The Ring doorbell now exists over three generations, and in at least two of those generations there are three different doorbells – one of which is substantially different from the other two in each case. It means that anything you find by Googling is likely to apply to any one of up to nine different models, and is heavily biased to the older generations, and the model that is substantially different in each generation. Even Ring’s own support pages are a convoluted mess covering multiple devices and multiple generations, with very little specific information covering equivalent issues for the latest generation. It’s also not helped by the fact that Ring assumes – and most people who install them apparently fall into this bracket – you will want want to wire them up in parallel with existing doorbell systems and chimes. I wanted a clean and independent install, and it would appear that I am the only person in the entire known universe who did.

At this stage, with the dodgy live view issue, the doorbell was connected to 2.4GHz, and the Chime Pro to 5GHz. However, when I switched the doorbell over to the Chime Network – thus eliminating 2.4GHz on the extender altogether – the whole system is working flawlessly again. And with a strong signal all round. Basically, I have the doorbell connected to the Chime Pro, the Chime Pro connected to 5GHz on the extender, and the extender connected to my home network. And since I will be needing another Chime, I am anticipating that connection directly to the Chime network will be easier than having to fiddle with the other stuff when I do.

From what I can gather, the Chime Pro (and possibly even the doorbell, though I didn’t experience issues with that) is very sensitive to what network options it sees when you are setting it up. One piece of advice I saw this afternoon recommended running set up on the app in Aeroplane Mode so that the phone signal is off. In my case, it is possible the 2.4GHz signal was suffering interference from the other stuff I have in the house, or even that the extender uses a different protocol that was causing issues. I don’t know. All I do know is that I’d forgotten how much I dislike tinkering with networks, and why I dislike tinkering with them!

Anyway, if anyone approaches my front door now the Chime Pro gives an audible warning downstairs, I get one on my PC upstairs, and an alert on my phone. You can select which sounds you get, and which devices give alerts (or not). This is useful, as I discovered this morning at 1.43am, when our milkman made his delivery and the system gave its chime for that! Or at 4.45am, when the paperman delivered the newspapers (and stared right into the camera)! The same is true when someone pushes the doorbell. In both cases, the doorbell records video in HD and saves it to the Ring cloud. You can set motion zones so it doesn’t pick up people walking on the pavement, and you can set it to distinguish between humans and vehicles (not tested that thoroughly yet). You can also set up schedules, so that it won’t sound at times when you tell it not to.

The doorbell also switches automatically to infrared recording when light levels fall at dusk. In this case, recordings are in black and white.

By itself, the doorbell is battery-powered. The battery lasts for a long, long time per charge, but it also takes a long, long time to recharge it. About ten hours, in fact. So you’d need a second battery unless you were prepared to be offline while you were recharging (and there’s a small security screw that’s just itching to get lost that you have to take out in order to remove the battery, unless you want someone to steal it). However, you can hardwire the bell so that the battery is trickle-charged permanently – the bell still runs off the battery, but the hardwire keeps the battery charged up.

All in all, if you can live with the fact you have to drill holes in your wall or door frame, run a wire to a suitable power outlet if you want permanent power, and fiddle around with possible network issues, the Ring Doorbell is an excellent security device.

Oh. And I should mention, you can have people fit them for you.

Damned If They Do…

25/09/2020

DOAADI

Computers & Tech, COVID-19, News

My feelings on this government, the Tories in general, and Brexit are well known. But I don’t go so far as to blame them for everything. Only the things they do wrong.

The new Test & Trace app is now available. I downloaded it with no trouble, and it runs with no problems that I can see on my HTC U11 (come on, HTC, I want a new flagship) from 2017. All you have to do is enter the first part of your postcode and allow a couple of permissions and it is set up. However, the way the app works means that it has to be installed on relatively new phones which have the necessary Bluetooth features on them. Note that I said the necessary Bluetooth features – not Bluetooth per se. The iPhone 6, for example, was released in 2015, and Apple stopped supporting it and earlier models this year. So in other words it is obsolete, and no one in their right mind should automatically expect any new app to run on that phone.

The Test & Trace app doesn’t.

Matt Hancock has gone on record as saying an ‘upgrade’ maybe needed to access the app. Rightly or wrongly he’s going to get slated for this. It’s his ‘let them eat cake’ moment. But how is it his problem? It’s like complaining that you can’t play a C60 cassette in a CD player, or a VHS cassette in a DVD machine (though it’s worth pointing out people did complain when those two things were current issues).

I’m not saying the app is perfect, or that it works properly – I don’t know, and time will tell – but the vultures are out in force over it simply because they can’t download it on to two tin cans joined by a piece of string. It only works on iOS 13.5 and later – and that counts for 70% of the iPhone-owning public. It will only run on Android Marshmallow or later – again, from 2015 – and that covers over 80% of Android users. It doesn’t run for the tiny minority using Windows, Blackberry, or anything else. It doesn’t run on phones which aren’t ‘smart’ (think ‘original Nokia’). And you can’t use it if you don’t have a phone at all – and believe me, there will undoubtedly be some people who are in that bracket who are complaining.

Dashcams and MicroSD Cards

31/08/2020

DOAADI

ADI, Computers & Tech

I first published this in 2019, but recently noticed people having dashcam issues which are likely connected with this topic. The original article follows.

A bit of advice to anyone using a dashcam. I see a lot of people complaining that theirs is playing up, and other advice to regularly reformat the card – which seems to get a lot of people recording again, at least for a while. I strongly believe that part of the problem is with the card, and not the dashcam. Specifically, people are using the wrong cards – and that’s true, even if they’re the ones their camera’s manufacturer is recommending.

I have always used SanDisk Extreme cards in my dashcams, and I have not had any problems. Extreme cards are not the cheapest, either. They’re pretty high spec. However, as a result of something I’d read online, I wrote to SanDisk and asked them if Extreme cards were OK to use in such dashcams. Here is what they replied:

Thank you for contacting SanDisk® Global Customer Care. Please allow me to inform you that for Dashcams & security surveillance cameras, we recommend to use SanDisk® High Endurance Memory Cards since these cards are specially developed for high endurance applications and continuous read & write cycles. These cards are built for and tested in harsh conditions and are temperature-proof, shock-proof and waterproof.

Also, please be informed that using Extreme or Ultra line memory cards on these devices void their warranty.

The text in that last sentence has been emboldened by me. At this point, it is worth noting that “high endurance” cards are special cards. They’re not easy to get hold of except through specialist suppliers, and your local PC World or Currys branch is unlikely to have them in stock. They cost more than normal cards.

But the upshot is that using Extreme (i.e. high-end “normal”) cards puts them under stress that they’re not designed for. It voids their warranty, but – more importantly if you read between the lines – there is a good chance they will malfunction or play up. I don’t know much about cards from other manufacturers, but I would lay odds that most people with dashcams are using the cheapest card they can get their hands on, and that means they’re not “high endurance” types – and probably not even branded. Most of the time I see people asking what dashcam to choose they always want a cheap one, and the one they end up buying often costs them less than I pay for a SanDisk Extreme card – so there’s no way they’re going to buy a card even close to that.

My current dashcam is the NextBase 612GW. It records in 4k, and on cards up to 128GB (so I get about six hours of footage in a write cycle). I have never had any problems with Extreme cards, but after the SanDisk advice I invested in a couple of Samsung 128GB high-endurance cards. I wanted SanDisk, but at the time they didn’t do them above 64GB. However, they do now (including a 256GB one) – and they’re reasonably priced, too.

When I originally wrote this, NextBase would not enter into discussion over the matter when I told them what SanDisk had said. They recommended using Extreme cards, and were (and still are) adamant that they work. However, I have noticed in their latest camera documentation that they strongly advise use of their own branded Class 3 cards, and point out that these are more expensive because of the extra work they are required to do. They don’t provide detailed specs, though, so I can’t say if they’ve used higher-rated cards than Extreme. At least you’d be covered under NextBase’s warranty if the card failed, so you’d have that extra level of security – which is missing if you use a SanDisk Extreme card.

I don’t disagree that Extreme cards have worked well for me, and they probably do for most other users, especially when they’re new. But the niggling problems people keep reporting are nearly always card-related. NextBase isn’t doing itself any favours by recommending Extreme cards (or if it is rebranding them), because if the camera doesn’t record people immediately blame… the camera. And even if it is shown that the card is faulty – even if they have been using one that cost them nothing and came in their cornflakes – they still blame the camera.

The bottom line is that SanDisk have told me very specifically that Extreme cards are not suitable for dashcams, and that using them for such voids their warranty. You cannot get much clearer than that. And it stands to reason that if you’re doing something that voids their warranty, the chances are it isn’t actually very good for them – and they break.

Does size matter?

From the same brand, probably not directly. However, if that brand tends to cause problems at some stage, then a smaller card will be over-written more frequently, and if the problem is ultimately related to over-writing a smaller card will present problems more often.

Does the brand matter?

You get what you pay for. If you buy cheap unbranded cards, compatibility and reliability is likely to be an issue. It’s no different to buying an unbranded kitchen appliance instead of a well known make to save money. You might get lucky, but if you don’t you have warranty issues and a non-functioning device.

Some unbranded cards may be fine. But not for everyone – you have to consider who made the camera. I use Nextbase, who are a major player, and they are very sensitive to the card manufacturer (as are most cameras, except that the cheap foreign ones don’t mention it, and you have no support if you run into problems). NextBase even go so far as specifying SD card model numbers which have been tested, so some SanDisk ones work, while other SanDisk ones might not.

Webcam Shortage? AUSDOM AW615

28/07/2020

DOAADI

Computers & Tech, News, Reviews

Until I saw this article on the BBC, I had no idea there was a webcam shortage. But apparently, the lockdown has meant these, too, have been panic-bought into oblivion, and they are difficult to get hold of.

During the lockdown, I’ve been having a nightly Skype session with my mate who lives in Leeds. Initially, we were just doing voice, but he upgraded his laptop and we were then able to do video calls. However, although my Surface Pro laptop has a camera, I prefer to use my desktop.

Over the years I’ve had several webcams, but since I didn’t typically use them much they inevitably ended up being put in a box somewhere and forgotten about. They were always oddly-shaped things, too. All curves and funny angles – and far, far bigger than they needed to be. This time around, I started looking for a simply bullet-style camera that could sit on the top edge of one of my monitors without it wanting to break into a song and dance routine and flash pretty lights at me for no apparent reason if I was on Facebook or something. I also wanted HD.

One of my preferred brands is Logitech. However, their HD cameras have all the usual angles and curves, with the added ‘benefit’ of being the size of an iPhone thanks to whatever fancy additional features Logitech is trying to sell to nutjobs who post on Instagram and Tik Tok every five minutes. I just wanted a camera – I have a separate microphone, anyway.

After more searching I came across a camera that looked like exactly what I was after on Amazon. The AUSDOM AW615.

It’s full HD, does 16:9 widescreen, and it does have a microphone (it’s also manual focus and wide-angle). For me, the most important detail was it’s shape and size – the camera itself is a short cylinder, and it has a bendy clip and bracket so you can put it in different positions on different monitors or surfaces. At that time, the price was around £70 (at the time of writing it is on offer at £50), but what I did then was take a look on AliExpress. It was obviously (to me, anyway) a Chinese device, and it was carried by many sellers on AliExpress. if I bought direct it turned out the price was $33 (about £25). So that’s where I bought it from. Incidentally, if you check out any of the models above, they’re cheaper if you buy directly from China – but it’s up to you.

It took about three weeks to arrive, but lead times are always a little longer from China anyway.

It doesn’t need any software – you just plug it in and Windows does what it needs to do to recognise it. As with any webcam, you really need to connect it directly to a USB 2.0 port on your computer, and not through any daisy-chain of hubs. If you do that, you’re likely to get problems, especially with a HD image at 30fps, which is this camera’s spec.

It works like a charm. Nice sharp picture, and you can do all the things with it that Skype lets you – blur background, add image, and so on. My boom microphone is better for sound, but the microphone on it works perfectly well. Definitely worth considering if you’re after a webcam.

Saving Money On Magazines

15/07/2020

DOAADI

Computers & Tech, Education, News

A couple of years ago I was having a clear out and I was amazed at the number of magazines I’d collected over the years. They were mainly my Classic Rock mags, and part of my decision to have a clear out was that I’d been getting more and more disillusioned with that particular publication.

At the time, I was on an annual subscription, but Planet Rock had just launched its own magazine and that did exactly what it said on the tin – it covered rock music. Classic Rock acquired a new editor, and she made it clear in her introductory piece what she was planning. Subsequently, any rock music they covered had to include at least half female acts – meaning it became obscure and far from ‘classic’, at best – and they also decided that (as just one example) Depeche Mode somehow ticked both the ‘classic’ and ‘rock’ boxes at the same time (actually, they decided twice in the space of just a couple of months with that one example). Then they did their ‘best 100 female artists of all time’ issue, and necessarily had to include non-rock genres to fill it out. That was it from me, and I cancelled my sub.

Before any feminists start frothing at the mouth over this, I go to see lots of female artists and bands with female members. I actually seek them out if I hear them on Planet Rock and like the sound. Like Samantha Fish, Haim, Paramore, Evanescence, Courtney Love, Joanne Shaw Taylor, The Lounge Kittens… I just don’t need any feminist magazine editors trying to filter out the men for me. And if you don’t like the fact that I don’t like that fact, click the back button and piss off somewhere else.

Planet Rock mag suits me fine, but when the lockdown came along, it also came with a lot of extra time for reading and finding tips on how to do stuff I wouldn’t have otherwise had time for. And going out to buy magazines wasn’t an option – even if it would have been of benefit with the ‘current’ issue on sale (you usually need a series of them).

A few years ago, as a result of my quest to find some authentic German food recipes, I came across a subscription service called Readly. It carries – and this is no exaggeration – thousands of UK titles. They’re all the ones you see on the newsstands (and many you don’t), from TV Times, OK!, Hello!, through all the photography and amateur DIY magazines, through to music and musicians (including Classic Rock). They cover specialist computer and technology subjects, gaming, weddings, cycling, fishing, horse riding, pets… everything (but no X-rated adult stuff). Including back issues, too, which multiplies the content by at least ten. And as I already implied, they have similar numbers of publications from Europe, Asia, and America. They’ve also recently started including newspapers, though it’s only The Independent and Evening Standard right now.

My normal Readly subscription is less than £8 a month, but they offer a two months for free trial. Even so, at £8 a month, that’s the newsstand cost of just three magazines! If you were after foreign magazines, you’d probably pay more than that for a single issue once shipping was included.

You can get the Readly app with the offer through Amazon (it’s free), and you can read on your phone, tablet, or computer. You can also read offline by downloading the content.

Air Conditioning In Cars

29/11/2019

DOAADI

ADI, Computers & Tech, Driving Tests, Training

This is an old article from 2013, but it is due an update. When I originally published it, one of the show-me-tell-me questions was:

Show me how you would set the demister controls to clear all the windows effectively. This should include both the front and rear screens.

At the time of updating, the relevant show & tell questions (they changed the name) are:

When it’s safe to do so, can you show me how you’d set the rear demister?

When it’s safe to do so, can you show me how you’d demist the front windscreen?

For the windscreen – that’s the one on the front of the car – the universally correct answer would be that you’d switch the airflow to blow out of the vents on the rear of the dashboard up at the windscreen, turn up the fan speed, and increase the temperature of the air from these vents. That would work for any car, although the actual knobs to twist and buttons to press will vary from model to model.

For the rear window, you’d turn on the electric heater that warms those little metal wires stuck to, or embedded in, the glass. There will be a button somewhere on the dashboard that turns it on and off.

You will note that the original broad question has now been changed to two rather more specific ones. This is relevant, because most newer cars also have air conditioning, electrically heated front windows, and often a button labelled as “MAX”, which turns everything on to demist all the windows very quickly at the same time. One press and you turn on the front and rear window electric heaters, the air conditioning, and redirect the hottest air possible at the windscreen (and often the side windows, as well, if your car has that feature).

When asked the original show-me-tell-me question, operating the MAX button was a perfectly correct response – as were playing around with the air flow controls, using the heated front windscreen if you had one, and turning on the rear window heater. However, with the much more specific Tell questions currently used, pushing the MAX button isn’t strictly the right response to either of them. It is also worth noting that whereas the original question would have been asked whilst stationary, if either of these new ones are asked, it will be while the candidate is driving. Ever since they started doing it this way, I’ve had nightmares about people fiddling with buttons and dials while taking a bend and losing control (I know the examiner would prevent that, but at the very least it would result in a test fail).

Arguably, operating the MAX button is a satisfactory response to either question, because it will achieve the desired result. But it is technically not the correct response if you’re being pedantic about it, because it does several other things at the same time.

It makes sense to understand all the controls rather than just blindly push buttons and twist knobs. If nothing else, if you inadvertently turn the car into a sauna, you ought to know how to turn the temperature back down again – and you’d be surprised by how many people can’t work out for themselves that if you turn something on by pressing a button or flicking a switch, you can usually turn it off by pressing the button again, or flicking the switch the other way. It also means that if you respond to the examiner’s question by pressing the MAX button, you’ll probably be able to recover if he specifically asks you to demist either the front or back – but not both.

How does the air-blower demist windows?

It involves a bit of science, but it is enough to know that hot air will demist windows, whereas cooler air probably won’t.

The reason it works is down to relative humidity. Air can hold water vapour as a gas, but if the amount of vapour reaches the maximum that the air can hold, it precipitates out – condenses – as water droplets. That’s the “mist” on the glass. The problem is that the maximum amount of vapour the air can hold before condensation occurs gets less and less the colder the air is. If you refer to water vapour in air as the “humidity”, then the amount of vapor relative to the maximum possible is the “relative humidity”. In summer, a relative humidity (RH) of 70% might feel horribly sticky and sweaty – but there’d be no condensation. In winter, you can easily get 100% without feeling it because there’s a lot less moisture there– but since there’s no room for any more vapour in the air, any extra causes condensation to take place. Think of it as a bucket overflowing, where the colder it is, the smaller the bucket is.

What happens is that on cold mornings, with the air at – or very closer to – 100% RH, as soon as you get in the car, breathing and perspiring, you overflow the bucket and condensation takes place. You see it on the glass as mist, but everywhere feels slightly damp. When you initially turn on the heater, it is blowing cold air, and if anything you get even more misting. But as the car warms up, it starts to blow warmer air. This warm air can hold more water vapour, and it evaporates the mist as it blows across it and keeps hold of it.

What does the air conditioning do?

Air conditioning (A/C) units pass the air over a radiator filled with coolant – just like what you have in your fridge at home. If you look back at what I said about humidity, above, you can probably work out that if you cool very moist air, you send it above 100% RH. The excess moisture – and if you cool humid air at 30°C down to 8°C, there’ll be a lot of it – condenses out (usually as a pool of water under your car in summer if you’re stopped), and much cooler and drier air is blown into the car. You can play around with the temperature of the air that is blown in by passing it over the heater radiator, so you have crude climate control.

Since it removes moisture, A/C is extremely efficient at demisting and preventing further misting.

How do the heated windows work?

In a similar way to the air blower. As they heat up they create an area around the metal wires which is warmer and so the mist evaporates back into the air. They work best in conjunction with the car heater, which heats the bulk of the air in the car, and which can then keep hold of the vapour, preventing condensation. They work even better with the A/C, because it strips the vapour out and dumps it outside the car. The MAX switch activates everything in one go.

How do you control these features?

It varies from car to car, but for the heater blower, there will be several rotary controls usually located in the centre of the dashboard and below the level of the steering wheel.

One of them controls the speed (and noise) of the fan, one controls the temperature (blue is cool, red is warmer), and another allows you to select which vents and grilles the air will be blown through (at your feet, at your face, at both, or at the windscreen – possibly with other combinations).

Higher spec cars may have digital temperature displays, and some will have independent control for each side of the car. Some will even have controls in the rear for back seat passengers.

The heated rear window button will have an icon like the one on the left, and the heated front windscreen will have one like that shown to the right.

The air conditioning will be activated with a button or switch marked A/C, and the MAX button (which activates all of these features) may also have one of the window icons.

Isn’t the heated windscreen for de-icing?

Not specifically, no. It serves the exact same purpose as the heated rear window – to demist. However, every demisting feature in the car can also de-ice if necessary. Even blowing cold air can lead to de-icing if it isn’t too cold, because the air passing through even a cold car is still warmer than that outside. However, a heated front window is noticeably useful at de-icing since that’s the very window that needs de-icing the most.

Having said that, a heated windscreen is only good at melting frost or dislodging a thin layer of rimed ice. If you think it’s going to get rid of a couple of inches of snow, think again. It doesn’t actually get that hot – if it did, it could cause the glass to shatter.

Why do my windows steam up in summer if it’s been raining?

That’s because water cools as it evaporates. If it’s already humid when it rains, the air passing over the windscreen evaporates the rain drops, so you get cooling around them. The humid air inside the car is then above 100% RH close to these spots on the windscreen, and condensation occurs. You usually see it around spots of rain.

You can also get it if you’ve had the A/C on. It cools the windscreen right down, so when you turn the A/C off and humid air gets back in, the cold zone near the glass sends the RH there above 100% and condensation occurs. In this case, misting is more uniform, but often concentrated on the lower part of the windscreen where the A/C has been blowing.

So what should I tell the examiner on my test?

Your best bet is to answer the question he’s asking you. If he asks how you demist the back window, operate the heated rear window switch or button. If he asks how to demist the front, either demonstrate how to redirect the air flow and increase the temperature and fan speed, or operate the heated windscreen button or switch (if your car has it).

In Nottingham, examiners have not been querying use of the MAX button, so use it by all means – but just make sure you know how to activate just one of the features as necessary if your examiner presses you on the subject. You are being tested on “safe driving for life”, so you ought to know what the buttons do anyway – you’re going to need to if you pass.

Since these questions are asked while you’re driving (and since you’ll be driving when you use them once you pass), be careful not to stare down and lose control of the car.

Ford Focus Yo-Yo Windows

17/11/2019

DOAADI

ADI, Computers & Tech, Transport

My Focus has one-touch electric windows. On my last car, shortly before it was due for a service, the driver-side window developed a fault whereby when it was closed and hit the top of the frame, it bounced half way back down. What I had to do was carefully inch it up and make sure it didn’t hit the top each night when I got home and locked it up. There was still a small gap, though, but it had a service booked and we had no rain, so it wasn’t an issue.

The dealer fixed it and simply said it had been “reset”. I had no further problems with it.

I have another car now, and it has started doing the same thing. It isn’t anywhere near ready for a service yet, so in order to avoid the inevitable assessment visit and probable brake bleed my dealer would insist on before fixing it under warranty, I looked into it a little further. And big surprise, it is quite common on Fords (and other makes, apparently).

From what I can gather, the reset procedure is to put the window all the way up holding the button, and then keep it held for 3 seconds. Then, push the button and put the window all the way down, then keep it held for another 3 seconds.

But that doesn’t work by itself, because as soon as the window hits the top of the frame, down it comes again. It seems to be connected with the safety feature that prevents idiot kids (and dogs) getting their heads squashed if the window goes up while they’re leaning out. A sensor detects the resistance and winds the window back down again.

The trick is to use a piece of paper or thin card when you do the reset. Hold it just under the top window frame recess and put the window up. Hold the button for 3 seconds. The paper acts as a cushion and prevents the sensor triggering. Now put the window down and hold the button for 3 seconds. That should now have reset the sensor and the window goes up and stays up.

It ought to go without saying – but I’d better say it anyway – do not use anything hard as your cushion, otherwise you’re likely to break the glass. Use paper, and fold it once or twice as necessary to get enough cushioning to stop the auto-retraction kicking in while you do the reset. And keep your bloody fingers out of the way when you’re doing it. Don’t say I didn’t warn you!

My windows bounce back when they reach the top

You may have a faulty motor or sensor, but from my experience it is most likely just needs a reset. Follow the instructions above. That should reset it.

My windows come down on their own

I have read that on some models there is a feature which automatically opens the windows when it gets hot – even when it is unattended, and sometimes in the middle of the night. I have also read that the windows in some cars can be controlled from the key fob, and this can get pressed whilst in someone’s pocket. The sources for this are various web forums, and are not really to be trusted, but even if such a feature existed, I can’t believe that would be available in the UK because the car would get stolen almost immediately in some areas.

It is possible you need to do the sensor reset without knowing it, and the windows actually opened before you locked it up but you didn’t notice. That’s just a thought, and I’m not saying it’s right. But the first time I experienced the bounce back I didn’t realise until I went out again and saw the window open.

If I woke up to open windows, I’d book it into my dealer pronto.

Nextbase Dashcams – 612GW

08/11/2019

DOAADI

ADI, Computers & Tech

I’ve had a Nextbase 612GW for over a year now (that’s the Amazon link there). It records in 4k – meaning that you can see number plates and other details much further away and much more clearly than on other dashcams.

I’m actually on my second unit. Within a year, my first one stopped turning on automatically, and after discussions with Nextbase, they gave me an authorisation code so that Amazon would accept the return and refund me. I bought another in lieu of the refund.

What had happened was that the internal battery had died. It would barely run for 30 seconds after a four hour recharge, and since it is the battery that provides the camera with enough residual power to detect when the power systems in the car are activated (which tells it to turn on and start recording), it was kaput. It worked perfectly if I powered it on manually each morning once a bit of charge had gone to the battery, but any power down lasting more than an hour and the battery would drain again.

Any 4k video device right now gets warm when it is in use, and the 612GW is no exception. I wouldn’t say it gets hot, but certainly very warm, and with the summer we had in 2018, it got warmer still. Li-ion and Li-Po batteries are degraded by high temperatures, and I suspect that overall this contributed to the battery going as quickly as it did. OK, it may also have been a bad batch (or just a bad one in my case), but I didn’t go into that with Nextbase. I’d had it replaced, after all.

It is worth noting that Nextbase told me replacing the battery is quite easy, and they supply them if you ask. It does involve a bit of soldering, but I will bear it in mind for the future.

As I understand it, some cheaper dashcams use a capacitor to hold residual power. However, where a battery is involved, this problem of degradation could occur with any model of camera. Indeed, any battery-based dashcam will effectively “break” sooner or later once the battery dies. Exactly the same thing happens with laptops, phones, and tablets – and it is amazing how many people don’t realise it’s just a dud battery which, in many cases, could easily be replaced. It even used to happen with desktop computers, when the coin battery which held the BIOS settings that enabled the PC to boot died (I’ve replaced a fair few of those in the past for people who thought their PC was broken).

I suspect that a lot of the complaints you see about dashcams dying could be a result of this – along with using the wrong types of SD card.