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when you’re running low on milk and then gets Tesco’s to delivery you 4 pints of freshly squeezed cow that is 3 days out of date?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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Arduino Morse Decoder #3 – Decoder Shield Build

So after playing with Asian QRP transceivers for the past few weeks/months it was time to get things back on track and crack on with all things CW & Morse.

After successfully building the LCD Shield portion of this project the next stage was the actual decoder shield.

Here’s the partially completed shield prior to making all of the necessary wiring connections.

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It was at this point I noticed there’s one all mighty faux pas in Arduino Projects for Amateur Radio. There’s no help with wiring up the components on the prototyping shield.

I started working my way through the circuit schematic  after a considerable amount of Google time looking for publishing errata, with zero success. After several hours and a growing spider web of pencil on my circuit layout diagram I decided to wing it and emailed the authors directly, as the publishers’ support page was less than useless.

In less than half an hour the below diagram which is missing from the book was emailed over by Jack (W8TEE) and Dennis (W6DQ). Nice one guys, much apprecaited!

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So after an hours fiddly work soldering up the necessary links it was time to test this thing.

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With a certain degree of regret I had to unplug my LCD shield which was occupying the only free USB port on my computer. It had counted 1837237 seconds since inception, which equates to 21.26 days. Anyway, moving on!

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With all the shields stacked up the prototype was starting to resemble the leaning tower of Pisa and preventing it from toppling was a pain. Application of a few stand off spacers on the Arduino helped with that.

I plumbed up a Y-splitter on the audio out from my PC, hooked it to the decoder and loaded up a test MP3 file from the ARRL Morse Practice Archive and waited to see what happened!

In two words “absolute jack!” A double check of everything revealed nothing obvious.

As Adam Savage of MythBusters would say “Failure is always an option!”

Arduino Morse Decoder #2 – LCD Shield build

Some people may ask why bother posting something as simple as this, but for the uninitiated it shows how simple this stuff can be and may spark some enthusiasm.

After having sat around for a few weeks waiting for a stray component or two to land I’ve eventually built the LCD Shield portion of this project. This will be the output display for the decoder and is pretty crucial to proceedings.

As this stage is purely development I decided to build the shield so that I could plug various LCD modules into it to try different sizes and colours etc. before hard soldering my chosen one onto a board.

With that in mind I substituted a header system to give plug and play options.

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The only snag with this is that the LCD is too heavy to self support purely on the headers alone and starts to sag quite alarmingly without some form of support!

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A 12mm M3 screw turned upside down with a nut located a few millimeters along the thread does the job quite nicely until I can find something a little more permanent.

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Aesthetically, once docked to the Arduino board this starts to look like a bad game of Jenga but this is purely prototyping!

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And as proof that everything works nicely here’s the Morse Decoder display 176 seconds into its existence next to the one I put together from my existing shields on 24th January. 1202472 equates to 13.9175 days! For some stupid reason I haven’t got the heart to unplug it.

Here’s the big brother screen (20 x 4) to the 16 x 2

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This has a much nicer feel to it, probably because it’s less cramped and I’m glad I didn’t flog it on eBay as I’d been planning to do. Just goes to show that disposophobia can be a good thing!

It is seriously heavy compared to the 16×2 screen and is currently perched on a 12mm piece of plastic pipe which I hacksawed off and placed between the back of the screen and the shield PCB otherwise it would have collapsed taking the pin header with it!

Arduino Morse Decoder #1


When all this interest in radio started a few years ago I remember putting something similar to “amateur radio project kit” into Google in the hope of finding something to build which would teach me a few things. By chance I plumped for a Stellar WSPR decoder as per blog post #1, but in amongst those search results was the Cumbria Designs Microcode Morse Reader which eHams rate as top notch.

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It really is a case of “chicken and egg” on this one as if I’d have bought it and built it, it would have been a case of “well done but what are you going to do with it?” so it’s been on the back burner as an idea for almost 3 years. Now Morse code is starting to feature in my radio interest a Cumbria Designs Microcode Morse Reader would be a really useful piece of kit to have. Somewhat ironic that the bloody thing is now discontinued! If ever my sense of timing was well and truly out, this is one of them!

So after I recovered from smacking my balding head against a wall and making noises akin to Father Jack from Father Ted, I tried to work out what to do. OK, option one is learn Morse, but Rome wasn’t built in a day and a little help on that journey would be a good thing.

The whole idea of a unit which duly trots out a decoded Morse transmission would be a massive help in my learning, but what to do in the absence of the “Holy Grail?” Using a PC is one option but it’s not that portable, buy a cheap Chinese unit from eBay or adapt and overcome.

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These Chinese units are a bit of an unknown quantity and to be honest they’re probably a Cumbria Design’s knock off but there’s a complete absence of anything useful in the information department alongside the listings to give you a clue as to the why and how.

From scouring the images on eBay at a guess there’s a microcontroller in there, some form of Op Amp and a tone decoder which suggests that they’re akin to the Arduino projects that are out there already on the internet.

Now trying to be frugal, I’ve got a box full of Arduino bits and pieces that have been sat in the garage for a while. I started playing with these things a few years ago when they first surfaced on advice of a good friend and I had them doing all sorts of daft things like running Apache Web Servers and logging the ambient temperature to an SD card. I rapidly ran out of enthusiasm as I didn’t really have a use for them doing anything vital to the existence of mankind so mothballed them. Time to blow off the dust!

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A bit of internet trawling revealed a few ways of potentially doing this but my favoured option is from Arduino Projects for Amateur Radio.

I’ve tried to read a few books on Arduino over the years and never really got to grips with it but the above contextualises a lot of it and if anything provides motivation as there’s a real potential to get an Arduino earning it’s crust!

This will sound ridiculous to the educated out there, but I have never been able to get my LCD shield working. A 5 minute read of Arduino Projects for Amateur Radio and all becomes clear, you need to ensure that the pin assignments in the sketch correspond to the shield you use. My shield is a Nuelectronics LCD-Shield V1.1 (as I bought the cheaper clones rather than the genuine Arduino ones) and as such the pin assignment does not correlate to the example sketch provided with the Arduino IDE.

Armed with that vital bit of knowledge a quick Google of Arduino LCD Keypad Shield and bingo you’re rewarded with dfrobot’s site with an example sketch which shows you the pin assignment which works.

In brief you need to change the pin assignment in the sketch to read –

// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(8,9,4,5,6,7);

And the end result is, tada!

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Simple things please simple minds but hey who cares!

If anything that’s a confidence booster and has spurned me on to build a simplified LCD screen shield, initially based around a 2×16 HD4478 LCD

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and combine it with a Signal Processing Shield

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This should give me the basic system.

Stage two is to change the display to a 4×20 LCD and then finally stage 3, move the project off of the stacked Arduino prototyping platform and onto a dedicated board utilising a Prototino board.

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Having 90% of the required hardware immediately to hand is a bonus, so forwards and onwards!

In a similar manner WB7HFC along with countless others are way ahead of me on this one and it’s useful to have a reference point and to see what the end result could possibly be. The sketch of WB7HFC’s project is here for reference.