use a smart switch to turn off a lithium battery charger
I know that I ought not leave things powered on. Knowing that is easier than remembering that an e-bike or drone or laptop battery is still connected. Below I show how to turn on...
I know that I ought not leave things powered on. Knowing that is easier than remembering that an e-bike or drone or laptop battery is still connected. Below I show how to turn on...
The very popular, but hardly-known Xiaomi nightlight, which lights up a dark space when you pass, now has a ‘smart’ version. A night light is nice on a dark stairway and toe-saving on a...
A ‘smart scale’ that records my weight to a phone might be seen as ‘gadgety’ but when you’re dieting, a weight record is satisfying and very encouraging. A downside is that the scale doesn’t...
when you want an e-bike and you don’t want another bike:
, If you’re a casual electronics hobbyist like me, the idea of using a LCD magnifier or microscope may seem attractive. For example this music spectrum display kit requires soldering 240 SMD LEDs, with...
topics on this page: what do I eat? how does my weight change? do I get enough sleep? where did I go today? how does my body react to exercise? introducing Google Fit You...
If you’re looking for a smartwatch, look at the Huawei Watch / Huawei Band 6 / Huawei Watch Fit New wearables If you’ve yet to get yourself a smartwatch I’ll have a guess at...
… but then I found that I could see my Huawei data in apps such as Google Fit and Google Drive. With the Health Sync app acting as a go-between, you can connect different...
Why do this? At an early point on the journey to network heaven you may have a need to connect from some holiday location say, to a camera, your computer, a home automation setup...
how a light can be on when its switch is off I’ve a number of smart light bulbs that, in addition to a wall switch, can be turned on or off either by say,...
What’s going on? Hec, I’m in a room with robot arms and fingers twitching as they respond to social media. THIS can only be art but it’s art powered by makers. Tucked away is...
The Netgear Nighthawk r7000 is a router, switch and powerful Wi-fi access point in one unit and even in 2021, years on from when it was made it still offers your network a boost...
There are LED strip lights where every LED can be doing something different with the result that you can create peculiar effects. You can start with a commercially available kit but after a while...
The Home Assistant home automation hub is more useful if you can access it remotely. In addition to having anywhere access with a browser URL, there’s an excellent phone app to access Home Assistant....
If you need to access Home Assistant remotely away from home, skip this page and instead go to access your Home Assistant remotely using DuckDNS, Letsencrypt and the nginx SSL proxy. This page is...
Your smart bulbs, switches and door bell all come with a useful manufacturer’s app – over time you’ll accumulate many such apps. While Home Assistant might make them redundant, here are couple of tips...
The digits at one end of a large LED clock displayed much more dimly than they ought. I’d say they were about half the brightness – and it was quite a puzzle. The clock...
If you need to know when a device, like a dryer or washing machine has finished working, get a ‘smart plug with energy monitoring‘. Amazon list many of them but whichever brand you get,...
This ceiling ‘coffer’ is lit by four 5m LED strips cut down to size fitted in 2017. If you wanted really, really bright light, these analogue white LED strips were the thing to get....
If you use Home Assistant you can show temperature, time and other sensor entities on this cute display. The inspiration for this mini-project came from a need to display my oven temperature in a...
Without copying a screenshot to or using a USB stick (no!) All the day I capture useful or interesting images from facebook, instagram, desktop apps and web pages. I copy bits of images to...
Ovens may have digital controllers or analogue temperature controllers and cooks seem to have blind faith in their settings. In this household the cooks were burning food so I checked the oven temperature. It...
The measurements that I take around the home provide two things: – a picture of a moment in time – a room temperature for example. – how something changes over the course of a...
A home automation platform, such as Home Assistant, allows you to make temperature v time graphs using sensors that you might place around the home. Monitoring temperatures allowed me to get my heating devices...
Yes. Below you’ll see how to control HomeEasy devices through Home Assistant and the RFlink receiver/transmitter. (This also controls other manufacturers’ wireless sockets). You’ll be able to create timers and automation to turn things...
or how to selectively expose Home Assistant entities to Alexa with emulated hue Home automation platforms like Alexa, Google Home and Home Assistant show major differences in the devices that they can discover and...
If you want to use a GitHub project with Arduino software follow this step-by-step guide. We’ll make an ESP32 camera web server using the Github code from ‘easytarget’. An ESP32-CAM module consists of a...
I discover my bicycle headlamp wasn’t working because some 18650 batteries have a button top. Oh my, that was embarrassing to admit The 18650 ‘battery’, like many batteries, is named according to its dimensions....
Here’s what to do when a restaurant asks you to scan a QR code for their track and trace (written in 2020). And here’s how to identify a plant, an animal and lots more....
The need: you use a table light for watching TV and a main (wall) light at other times and you want a coffee table button to switch between one or the other or have...
a 3-gang wall switch for your home automation – using eWelink, T4EU1C and Home Assistant I got to a point where I had plenty of ‘smart’ lights and gadgets but few switches. But then...
in this project we integrate inexpensive 433MHz RF devices with modern smart devices see also: 433MHz smarter letterbox how to set up RFlink so that it will read your RF sensors The easiest ready-to-go...
In a previous project I set up temperature sensors in my room and sent the data via Bluetooth to Home Assistant, the home automation platform. Home Assistant is software that can record measurements and...
Toggling a light switch means that a press of the switch will turn the light off or on depending it what it was last doing. There is nothing clever about that but if I...
I wouldn’t especially recommend the D-Link DCS-D150 motion sensor but it does have some features that had me buy it. Firstly it plugs into a wall socket above a worktop so it can sense...
If you could look inside an old replaceable laptop battery pack like this you’d find 4 or 6 cells. Usually the cells are 18mm diameter, 65mm long and are called 18650 lithium batteries. Each...
‘Smart meters’ and metering devices usually measure the electricity used by the whole house*. However I prefer to pay attention to the electricity used by individual devices, such as a combination oven, fan heater...
In this project I control a Sonoff light switch using Home Assistant. You can do the same with other Sonoffs. The switch shown here is the T4EU1C wall plate switch. It works over wifi...
The regular way to switch a Sonoff relay is to use the official ewelink app. Other ways require you to ‘flash’ the Sonoff device with Tasmota or ESPHome software and then control it with...
The Home Assistant dashboard (aka ‘Lovelace’) is very good at displaying live sensor data as well as historic sensor data. The display below shows a ‘just now’ reading of the sun and also a...
How to make inexpensive, ‘old’ technology, 433MHz devices work with today’s smart devices see also: 433MHz smarter letterbox RF sensors and receivers If you’ve used any of the following examples you probably own some...
smart sockets have uses. A smart socket adds a little cleverness to a table lamp or electric heater. The printer upstairs takes five minutes to warm up so switching it on by remote control...
How do I safely house an electronics project? Is there a better way to mount a ESP-CAM camera? I’d been looking for boxes in the wrong shop so I found a better shop. My...
they work together but not everything is possible As an early adopter I’ve come to feel that Philips Hue lighting system gains more praise than it needs. Dozens of other makers now do pretty...
see also more about 433MHz devices The letterbox is five doors and fifty metres from my desk. The uncertainty of the post lady arriving in the afternoon means that I make wasted journeys to...
This quick post is for anybody wondering how much money they need to put aside for energy. If you don’t use electricity for keeping warm, your summer and winter electricity bills will be similar....
smart bulbs and sockets have select uses. A smart socket adds a little on/off cleverness to a table lamp, electric heater or the printer upstairs that takes five minutes before it’s warm and useful....
When you look for home automation equipment you find many systems. They turn on lights and plug sockets; water the garden; unlock a door, turn up the heating; record a security camera, open the...
In the beginning there was the smart bulb that changed colour and convinced me that here was something trivial and fanciful. Today I’m surprised by the usefulness of the smart gadgets on sale. There...
… and see how to add features to the Home Assistant display An interest in solar energy is a possible reason to record the sun’s azimuth and the time of sunset. Home Assistant can track...
The Google nest thermostat (or its Hive equivalent) are devices which I’d be happy to pay for and recommend. I could easily make something that turned on the heating with temperature as it is...
When you set up a gadget or device you’ll sometimes be asked what its IP address is – and gosh – becoming at ease with that question is good for you. Every gadget connected...
what’s needed to start using ESPhome? option 1: an ESP32 development board with a micro-USB socket option 2: an ESP8266 development board – less power use, but no Bluetooth option 3: an ESP32 development...
Home Assistant is software that connects smart devices. It enables them to have a useful life outside of the app that they come with. You will gain unusual flexibility where a Philips Hue lamp...
Arduino IDE is software that lets us develop code for a writing on a chip. Explore its menu and we soon see it’s made to transfer a great many capabilities to a great many...
rogerfrost.com is a compendium of ideas for using technology with sciencey questions in mind. Started in 1995 to offer ideas to school science teachers, Roger Frost expanded the coverage to home automation, gadgets and sensors to monitor, or understand, what’s going on around us.
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Roger Frost has been writing since 1988 and this web includes his published articles about the use of the Internet; the work of scientists and how technology is useful at home or school.
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