Empyrean, Etherkit, OpenBeacon Mini

OpenBeacon Mini Status – Early June 2018

It’s time for a brief update on how things are going with OpenBeacon Mini, the successor to the OpenBeacon MEPT that’s been a long time in the making. For those who are unfamiliar with the new project, allow me to give a very brief overview of its capabilities. The OpenBeacon Mini is an automated transmitter for amateur radio operators that allows for automated transmission of messages using propagation study modes such as WSPR and QRSS, along with many of the other JT modes and CW as well. The carrier is generated by a Si5351A clock generator IC which is fed with a TCXO reference clock for frequency stability. Low-pass filter plug-in band modules allow operation on any single band from 630 meters to 2 meters. The OpenBeacon Mini detects which band module is inserted and sets the frequency accordingly, making band changes as easy was swapping out a plug-in module. The power and a data connection is provided from a USB micro B connection to any PC. Accurate time synchronization is accomplished through this connection, as long as the PC has time set through NTP. The user interface is a 128 x 32 px OLED display and 7 pushbuttons. As always with Etherkit products, all firmware, hardware design files, and and software is open source. Extra pins from the microcontroller and extra clock ports from the Si5351 are broken out for use in experimentation and expansion.

Something like this project has been on the back burner for a long time, and is finally now able to see the light. I intend to launch this as a crowdfunded product at the same time as my Empyrean microcontroller, which is at the heart of the OpenBeacon Mini. The Empyrean is an Arduino Zero derivative in the form factor of small DIP module perfect for breadboarding. I’ll have more about this initiative to post on the blog in the near future.

My first beta tester, LA3PNA, recently received his OpenBeacon Mini and had a chance to put it on a NVIS antenna for a few hours on 60 and 20 meters. As you can see from below, he received plentiful WSPR spots in that short amount of on-the-air testing.

I have another early beta tester working on getting his OpenBeacon Mini on the air soon as well. I am looking at getting one more early beta tester going with this PCB spin, just so that I can be very sure that the next PCB spin will iron out all of the kinks. If you are familiar with MEPTs, using the Arduino environment to compile and load firmware, and don’t mind a little bit of firmware roughness, I’d love to have you on board. Send me an email to milldrum at gmail dot com to let me know you’re interested.

This weekend, I plan to get OpenBeacon Mini going on 6 meters in order to see how it performs there. It should be a perfect time, since it’s also the weekend for the ARRL VHF Contest. Keep an eye on my Twitter account and this blog for further updates on this project.

Etherkit, Meta

Another Shack Cleaning!

Guess what? I realized that I had a bunch of microcontroller dev boards and such that I was probably never going to use, so I figured it would be time to put them up for sale, along with some other miscellaneous electronics stuff as well.

Please peruse my listing on my For Sale page!

Also, for a limited time, I’ve decided to bring back my old EtherProg AVR programmer, this time as an assembled product, lovingly built and tested by me. Only $9 plus shipping! Cheap!

Arduino, Etherkit, OpenBeacon Mini

A New Arduino Library Appears!

Since I’m waiting for circuit boards for OpenBeacon Mini to arrive, I want to keep the waiting time as productive as possible, so I’ve been working on the firmware. Specifically, one of my recent goals was to factor all of the modulation code out of the spaghetti mess that is the current state of the OpenBeacon 2 firmware (which is my starting point for OpenBeacon Mini).

In that vein, today I managed to finish up work on release v1.0.0 of the Etherkit Morse Arduino library. The majority of the coding work was done during my last few Twitch livestreams, so other than tweaking and cleaning up the code, most of the work today consisted of creating documentation and getting the repository in shape to be a proper Arduino library.

The way that this library functions is quite simple. Since timing in Morse code sending is critical, the end user of the library is required to provide a function that calls the library’s update method every one millisecond. This type of interface was chosen so that the library can be platform agnostic (since Arduinos come with different microcontrollers which have totally different timer functions). An transmit output pin and speed in words per minute is specified when the class in instantiated, and then all you have to do is call the class’s send method to send Morse code on the digital output pin. Alternately, you can have your sketch poll the class’s tx variable and act on it accordingly. Pretty easy stuff.

I’ve put in a request for the library to be included in the official Arduino Library Manager, so if you want to give it a try, wait a day or so for it to be listed there. If you really can’t wait, there are instructions in the README about how to manually install it. Hopefully you find it useful, and as always, please file your bug reports and suggestions for improvements as an issue on GitHub. Thanks!

Etherkit, OpenBeacon Mini

OpenBeacon Mini Proto PCBs On The Way

If you watched my previous Twitch stream, you may have seen that I completed the layout of the first PCB spin of OpenBeacon Mini. Today I ordered the PCBs from DirtyPCBs, along with boards for my low-pass filter module, and more Empyrean boards in anticipation of wider beta testing soon.

I wanted to get these boards to the fab before we started to run into the wall of Chinese New Year (which I seem to do nearly every year). I think I’ve ordered them plenty early, and even paid a bit extra for express shipping, so hopefully they’ll be in-hand around the beginning of February.

In the mean time, I’ll be working on some more coding for the OpenBeacon Mini on my Twitch stream and some other ancillary stuff while I’m waiting for the boards to arrive. Stay tuned for further news on this blog.

Empyrean, Etherkit

OpenBeacon Mini Proto PCB Layout Complete


I managed to finish the layout of the OpenBeacon Mini prototype PCB in KiCad this evening while livestreaming on Twitch. A 3D rendering from KiCad is above. It looks about how I sketched it out and wasn’t too nasty to route, so I got that going for me. So I’ll get on order off to the PCB fab soon. I’d like to get some PCBs completed before Chinese New Year, so I can’t delay very long.

While I’m waiting for my PCBs to be manufactured, there’s still plenty to do. Twitch streaming is kind of nerve-wracking for me yet kind of fun, so I plan to do more. I have a little more gear on the way that will allow me to also Twitch stream from my workbench, so that you can spy over my shoulder there as well. I even have a USB webcam for my microscope so I’ll be able to connect that to Twitch for your viewing pleasure. Stop by sometime on the livestream and chat me up.

Etherkit, Twitch

Twitch Success

I’m happy to report that I managed to pull off my first Twitch stream today, and even got a handful of viewers. There were some initial problems, as I was trying to stream at 1080p, but my wifi connection from my office just couldn’t give enough bandwidth for that to work. After restarting with the stream set to 720p, people were actually able to see my stream. Today’s work was on OpenBeacon Mini. I assigned footprints to the netlist and made a first pass layout of the PCB. I do intend to stream again soon, perhaps even tomorrow. Hopefully I’ll be able to finish the PCB layout on the next session.

Find my Twitch channel here and be sure to follow me in order to get notifications, thanks!

Empyrean, Etherkit, Meta

The Road Forward

Per my last blog post, I’ve completely deleted my Patreon account. Those days are over and are not coming back. I’m still not sure what will replace it, or if anything will. It is already difficult for me to ask for money in return for mostly intangible benefits. Losing the Patreon monthly income will hurt a bit, as that was the funds I was using to pay for OpenBeacon Mini (and other project) development. I only sell a modest amount of the Si5351A Breakout Boards via Etherkit; basically just enough to pay for keeping the lights on there for now.

So allow me to start using this blog again for what I was doing on Patreon, sans the locked content.

OpenBeacon Mini has a schematic finished and I’m just about ready to lay out the PCB. Empyrean (my Arduino Zero derivative) testing is going to be delayed a bit while I figure out how to fund the beta batch. Those two projects are going to be my main focus and I hope to be going into release with both of them by Q1 2018. Further down the line, I don’t want to speculate too much, but I’ll probably tidy up and finish some half-finished smaller boards that I want to add to my Etherkit lineup in order to fill out the catalog with some more RF products.

I’ll work on ramping up the blogging here, using my own site much as I was using Patreon: to post smaller updates about project progress. I always felt the need to make more substantial posts here, which often deterred me from writing. I believe that was a mistake. Expect to see more content in line with microblogging here in the future. Thanks for hanging in there.

Arduino, Etherkit, Microcontrollers, Test and Measurement, Test Equipment, Wideband Transmission

Wideband Transmission #10

OpenTechLab

If you’ve been reading my blog for any amount of time, you’ve probably observed that I’m a big fan of all things open source, especially on the hardware side of things. One area where OSHW seems to be lagging a bit is in the test & measurement department, so it was a very pleasant surprise for me to stumble upon a fairly new channel on YouTube about a month ago.

As you can see from the first video, the presenter (sorry, I couldn’t find the name of the bloke who makes these videos) gives an overview of the cheap logic analyzers on the market that can be loaded with open source firmware and then gives a very detailed demonstration on how to use the devices with the nifty open source Sigrok T&M suite (especially the PulseView GUI tool) and how to use a Linux environment and scripting to take measurements.

If you have any interest in this space, this is definitely a channel to which you should subscribe. There is also a show notes site that has links and other resources for the videos.

Using C++ in Arduino

In another case of me stumbling upon something which takes me down a rabbit hole, last week I was watching coding videos on YouTube when this one was recommended in the comments of another:

It’s quite a long video, but if you have any interest in coding and are an old fart who grew up with 8-bit personal computers (or are at least a fan of retrocomputing), then the time will pass quickly on this one. It sounds crazy, but the presenter (Jason Turner) of this talk was able to make a game for the Commodore 64 in modern C++! The way he did it was to create a tool to convert from the 80386 flavor of x86 assembler to 6502 assembler (well really 6510 in this case), which apparently is more feasible than you may think. His development environment is an online tool called Compiler Explorer, which for some reason I only learned about with this video. It automagically spits out assembler from C++ compiled from a variety of different compilers. In this case, the Turner created a custom local version of this tool to do the 6502 conversion.

I was gobsmacked at multiple times in this video. Many of the newest C++ features (from the C++17 standard) were used. With some careful coding, Turner was able to produce code with literally no overhead from all of the C++ features. The compiler was able to optimize many lines of C++ down to a handful of assembler op codes. Just watch it, you’ll be amazed as well.

This video, in conjunction with the series of posts that Hackaday has been running about using C++11 in Arduino, has convinced me that it would worth it to investigate the use of C++ in the Arduino coding environment. Arduino library coders already have to use a base level of C++ when they write for the ecosystem, but most people who write sketches do it in vanilla C-style (well, the bastardized Arduino version of it anyway). After seeing that talk, I had a lot of preconceptions of C++ overhead blown away. The ability to use the modern features of C++11 sound tempting indeed, so I plan to do some investigations into the feasibility of incorporating more C++ patterns into Arduino sketches, and I’ll be posting my findings here. Stay tuned.

KiCad PCB Rendering Tool

I have a habit of skimming my RSS reader (yes, I’m one of those old fogies who still uses one) in the morning while drinking my coffee, opening tabs of interesting things to examine in further detail later, while simply reviewing the rest of the new posts. Sometimes that means it takes me a bit to get back around to something intriguing among my many browser tabs.

Such is the case with this article from Hackaday. It’s just a short blurb about a new open source Python tool for making 2D renderings of KiCad boards. The attached demonstration image certainly looked nice. When I finally got around to downloading the code from GitHub and trying it out on one of my designs, I was pleasantly surprised. The script made a very sharp SVG rendering of my board, but unfortunately, there are only a handful of components in the PcbDraw-Lib library, which meant that most of my stuff didn’t get rendered.

Since I’ve been looking for a way to make nice illustrations of my PCBs for documentation and promotional purposes, I decided that I’d invest some time in adding components to the library, since I think the project has a lot of promise. After about half a day of muddling through making component drawings in Inkscape by studying datasheet engineering drawings, I was able to output a complete render of my Empyrean board, which you can see above. I’m quite happy with the result.

I’ve got a pull request in for the components that I’ve created so far, and as I continue to use the tool and fill out more of the library, I will continue to submit them upstream. While it’s still pretty rough around the edges, this project gets a strong recommend from me.

Etherkit, Microcontrollers

Market Research

It has been awfully quiet on the public front here for sure, but I have been working on quite a bit of things behind the scenes here at Etherkit Galactic HQ. It’s been a challenging year since I last wrote about the personal things going on here, but things have been going reasonable well after a rough half-year immediately following that post. I’m just about ready to attempt to revamp Etherkit, however there are still a few challenging roadblocks to overcome, and I could use a bit of guidance.

The most difficult issue is trying to re-bootstrap the business financially. I’m currently only selling the Si5351A Breakout Board, which obviously isn’t enough to expand a business upon. The possibility of a capital infusion unfortunately broke down, and so the only practical way forward at this point is most likely another crowdfunding campaign.

As mentioned in the opening paragraph, I have been working on various projects, and so I do have some candidates. Many of the projects that are in the works or only even in the planning stages require the use of a microcontroller, and so last year I decided to make my own Arduino-compatible microcontroller board family which I can then use as the heart of many of these products. I’ve taken a real liking to the Arduino Zero because of its speed and features, but the cost is fairly high and the standard Arduino form factor isn’t great for many purposes. Therefore, I have decided to make a new standalone board derived from the Zero which I call Empyrean, and you can see in the photo at the top of the post. It comes in two flavors: Alpha and Beta. The Alpha is based on the Atmel ATSAMD21G18A microcontroller, same as the Arduino Zero. The Beta uses a controller (ATSAMD21G16B) with a bit less flash and RAM than the Zero (but still more than an Arduino Uno), but is also priced similarly to the ATmega328 line of microcontrollers. Both come on a small board similar in size to the Nano and has nearly all of the same circuitry of the Arduino Zero except for the EDBG support.

It is true that there are a flood of Arduino clones out there and this makes entering the market with another one somewhat crazy. My value proposition for Empyrean is based on the confluence of breadboard-friendly form factor along with a wallet-friendly price. My target price point is around $15 for Alpha and $10 for Beta. While that is a fair bit more than your typical eBay Nano clone, Empyrean would also be quite a bit more powerful than a Nano, in both clock speed and available memory. So my question to you, dear reader, is whether you would be interested enough in this product to back a crowdfunding campaign in order to have it made? I do plan to make a serious push on a radio soon, but it would be nice to ramp up the business before that, while also solidifying the microcontroller platform that will be used in future products. Let me know what you think in the comments, or send me an email.

In the mean time, I thought I’d let you know that I’m working on a Rev D board spin of the Si5351A Breakout Board. You can see a prototype in beautiful OSHPark purple above. The most significant changes in this revision will be to change the coupling of the reference oscillator to the Si5351 XA input pin to meet datasheet specs and to panelize the board in preparation for future pick-and-place operations (they are currently hand-assembled!).

Perhaps even more interesting is that I also hope to be able to soon offer a frequency calibration report with every board sold. Thanks to LA3PNA, I am now in possession of a decent 10 MHz GPSDO to use as a lab reference, which will allow me to measure the frequency correction value accurately enough for hobbyist usage. I now have a small printer on hand, and so now what I need to do is add new code to my board test script to measure the correction value and print it for inclusion with each board sold. Stay tuned for notification when I’m ready to go live with this; hopefully soon.

Let me reiterate: I’d love to hear your thoughts about the above proposals. I’m interested in serving the needs of my customers. Thank you!