Wemos D1

Not to be outdone on micro controller usage, I am onto yet another micro that is worth using. I cannot see any real use for say ham radio, but for some other electronics projects i have been tinkering with for way to long, this might just be the go. The Wemos D1 is a uno compatible board that has 1meg flash, 80K ram, 80mhz processor and best of all WIFI, which means i can use this as a webserver for the weather station i have been planning/tinkering/building or procrastinating about for way to long. So with the addition of my other code and the hooking up of some sensors, I should be able to make this thing chooch and display the data on the world wide interwebs.


Going Light Weight

Well its the pigeon pair. I got the matching tuner to go with the HB-1B. The plan is to use it with a SotaBeams 10m pole and vertical wire and a couple of radials with the HB-1B and the Bitx 40 in some of the more space limited places I wish to operate from. I have everything here to acheive this, its just a matter of going down the local park with the laptop and antenna analyser and the rigs and getting things all sorted out.


STM32F103 Using Arduino IDE

So i have been trying to get this thing to play nice with the Arduino IDE. Its certainly not for the feint of heart and the thinned of skin as it will take some work and a lot of trouble shooting to get this nightmare to run and play nice.

Out of the box the board will not program via USB as the bootloader on the board is basic and requires an external UART programmer like the ST-Link V2. I do now have an ST-Link V2 but have one on the way from an ebay seller, but in the mean time i wanted to play with the micro and see how it performs.

So, with a serial programmer in hand and the 4 wires soldered in I burned a new bootloader that allows the board to be programmed via USB, then stuffed about with drivers to get ones that work and eventually uploaded the blink program and got it working.


The STM32F103 boards have a 72Mhz processor, 64K of Flash and 20K of Ram and a metric ton of interupts. Plenty of resources for everyday Joe’s like me.

Oh, and what ham radio project/s am i going to use this for? Well, you will just have to wait and see. I won’t be providing a full description of how to get these things setup and working either. If you really really really want to do it, you are just going to have to suck it up and do what I did. Spend 2 hours working out each and every problem along the way. Its not as simple as just plugging in your arduino uno board and hitting upload and I have no desire to answer 1000 questions on why something is not working, because what worked for me, might not work for you as it will depend on what tools you are using to make it happen.


600hz Tone Injection

So i was sitting here thinking about adding CW to the Bitx 4om. Now there are a number of ways to achieve this from unbalancing the mixer to tone injection. Tone injection seems like the easiest option for me currently and so I started to give some thought to where I am going to get my 600hz tone from.

Well, as I am already working on an Iambic keyer using an arduino, it seemed like the best place to start. It also turns out that this is also a very simple option as well as it really is just 1 line of code to turn a pin on and produce a square wave at the desired frequency with a 50% duty cycle.

And with some massive attenuation and some RC filtering, i should be able to turn this square somewhat sine and make it even sound nice.

tone (8, 600);

Can it get more simple than that.


Going Over To The Dark Side

Well its bound to happen eventually, the need to use SMD components. I have been collecting some now for a while and ammassed a tidy little assortment of these beasts. Best of all, they will all fit into 3 tiny ring binders. One for Caps, one for Resistors and one for Inductors and Semi Conductors. Might as well get in now and make a collection before all the large sized SMD vanish and only the grains of sand remain. I currently only have the one binder, but have 2 more on the way from China just to be sure to be sure.


M4070 LCR Meter

I have not had much luck with the inductance setting on LCR meters. Most of them are crap, inaccurate and just plane useless. I think this is the 5th cheapish meter I have tried and I have finally hit on one that works and works well. In the picture below is a 1.8uH slug tuned variable inductor. So yes, it works and is accurate and with 3 decimal places its going to be nice to use for getting those hand wound toriod inductors right. The test frequency is a bit low, it would be nice if it was in the MHZ range rather than KHZ, but for that you need to spend up big on high end gear, not $70 on ebay.


CW Transceiver Keyer and Keying

Ok, with my arduino woes out of the way, i can now focus on the transmitter part of the 3 band CW rig project. Cannot rush these things and i might even get this rig working before i die, well we all have goals to shot for. LOL.

So what do I need and how are we going to go about it. For a start I am a paddle guy, single lever paddle to be precise so I need some form of built in electronic keying. A fixed speed is all i need, say 15wpm, most of the people I work from parks are slower cw types so 15wpm is a nice speed. Memory keying would be nice as I will be using the rig mostly for WWFF or SOTA a basic CQ macro and CQ Sota and CQ WWFF are all i need build in. It needs to provide the sidetone and finally this needs to be able to key the transmitter on and off as well.

As far as arduino keyers go, the Arduino CW Keyer by K3NG is probably the duck nuts. Fully feature rich and does everything other than be the other half of your contact. I looked at it, tested it and its bloody awesome, but i really do not need all that complexity so I have decided to roll my own.


So i assembled some bits and bobs and started to write some code. I have it sending nice perfect 15wpm code already using the Piezo as the speaker. I probably will not release this code. I think if you want a full fledged keyer use the one by K3NG and if you are like me and just need a simple keyer for your project, then its time to man up and write some code. It is really not that difficult at all.


My Arduino Nightmare

A Tale Of Woe

So i got this brain wave that it would be nice to use bare IC’s in my projects rather than Uno or Nano board supported on headers. It all seems rather simple don’t it. Buy some IC’s with the bootloader already installed, drop them into your socketed Uno board with its on board AVR programmer and Bobs the uncle who touches you inappropriately at family gatherings.

But Oh No No No No, things cannot be that simple can they. Firstly, ebay is a minefield and while you are probably getting top quality IC’s and not chinesium grade floor sweepings, the term with bootloader can be somewhat vague. Yes the IC will take a bootloader, yes the IC may or may not come with a bootloader, but what bootloader is anyone’s guess.

So armed with what look like a pile of bricks and armed with your google foo, you start to look for answers on the world wide interwebs because the pixies are not going where they are meant to or doing what you want. And here armed with your vague error codes from the arduino compiler you find 100’s of people who have no idea how to fix the problem let alone what the actual case of the problem is telling you all sorts of bullshit. From the IC is bricked and cannot be fixed, from edit this file, edit that file, use a capacitor, use this method of wiring, that method of wiring, this programmer, that programmer.

Well I tried them all and guess what, none of these bullshit explanations made any fucking difference to shit. It all comes down to the stupid who is connecting things together. After trying 6 or so different ways of burning a bootloader i finally got one of the 4 different programmers to actually work, it sent the bootloader to my so called bricked IC’s like a pro and then went on to program some software on the IC as well and made an LED blink.

Oh and don’t ask me how i got it working, i really do not know, this programmer did not work the first 3 times i tried it and today for god knows what reason it worked. Thats arduino for you. I giant pain in the arse when things do not want to happen and a joy to behold when things go well. Your Mileage May Vary.