I’m back!

Contrary to urban myth and legend I’m still alive! Admittedly this is not a full resumption of service, but things are lurching slowly towards normality. Until a whole world of other things are completed, pretty much everything RF is on hold.

That said, there’s no point in making a post just to say I’m doing nothing – that’d be silly!

How about a little bit of on the cheap asset protection using the Internet of Things (IoT) to do something useful, unlike a fridge that knows when you’re running low on milk and then gets Tesco’s to delivery you 4 pints of freshly squeezed cow that is 3 days out of date?

I like the whole world of Instructables.com and came across a very nifty little post that seemed an ideal way to ease myself back into things and at the same time do something that I need at the moment – keeping an eye on the things I own!

There are two articles for this natty little device, the first gets you up and running and the second refines it beautifully.

I sourced the required door alarm unit and WiFi module from eBay for next to nothing and duly waited 3-4 weeks for them to land, but hey who’s complaining?

The ESP8266 WiFi module is tiny and a real work of art. With a few wires in place we’re set to go.

I plumped for a USB-FTDI module to program the ESP8266 as I couldn’t find my Arduino stuff in all the chaos and boxes around me. Again, a couple of quid from eBay.

And with it all hooked together, off we go!

I cheated a bit and used my laptop to search for the ESP8266 when it booted as a WiFi access point and then changed the IP address to my home network range so I could see it on my desktop machine via the built in web server which provides access to the inner workings of the module.

A real low baller came in the form of IFTTT changing the Maker Channel to Webhooks, which does exactly the same thing but isn’t called Maker Channel. That’s the problem when you play with this stuff late at night rather than go to bed, your brain lets you down.

So after a bit of desktop playing I had everything running nicely although it was as slow as hell using the ESP8266 BASIC program. Time to enhance!

ClemRz’s second post uses an Arduino script to do a slicker job and it’s a neat piece of code. Top tip, make sure you are using the absolute latest version of the Arduino environment (1.8.3) as I kept getting weird compilation errors until I upgraded it.

It works a treat and is much faster than the original iteration!

Now the next trick was to give the ESP8266 a home. The little $2 door alarm, for what it is, isn’t that bad. It makes a hell of a racket when it’s activated and would probably be useful enough on a hotel room door for slightly less salubrious stays, say the Days Inn Hotel on the M20 in Kent. But all we’re doing here is nicking the housing and the reed switch in effect. With the piezo sounder and the autotransformer removed from the PCB there’s plenty of space for the ESP8266 to cuckoo. This is a silent alarm which is neat as it adds nicely to the element of surprise on intervention as anyone sticking their nose into places they shouldn’t, doesn’t know that you know that they’re there!

So with a few breaking of tracks and soldering of wires it’s all done. You can just see the LED on the ESP8266 glowing. I kept it despite the minor drain it will cause on battery life just so I knew it was alive.

And there we have it – all done. I weighs about an ounce, is no more than 3.5″ long and 1″ wide.

When activated you get a very rapid email to whatever you want to access your email from notifying you of which alarm has tripped, time, location and battery voltage. I’ve installed the IFTTT app on my phone and have left the notifications for the app running. As such when one of my IFTTT applets runs I get an even quicker popup notification from the app that somethings activated without having to read my email.

Now I’ve got device number one working perfectly I’ll get it a few brothers and sisters to keep it company and put the IoT to some proper work!

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