In a bit of Etherkit news, we've encountered a supply chain issue that could put a squeeze on Si5351A Breakout Board with TCXO reference oscillator manufacturing. Late last year, there was a fire at the factory that manufactures many different oscillators, including the Abracon product that is used in the Etherkit Si5351A Breakout Board.

On Oct. 20, Abracon became aware of a fire at the Asahi Kasei Microsystem (AKM) semiconductor factory in Nobeoka, Miyazaki prefecture, Japan. Products produced at this factory are used in many Abracon TCXO oscillator products. At this time, there is limited information on the actual effect the fire will have on production and supply.

I have been able to acquire small quantities of the TCXO used in the breakout board until my most recent attempt. That particular part now is out of stock at all of my usual distributors, and is only available at one distributor but at a substantial markup from the usual price.

As of now, I'm considering the qualification of an alternate TCXO, but that will take some time to do. It may be necessary if Abracon cannot bring production back online in the near future, but I'm hoping they can source alternate manufacturers as is stated in the press release above. In the mean time, there may be a period where the Si5351A Breakout Board with TCXO is out of stock. The breakout board with crystal oscillator is not affected by this and will continue to be in stock.

Today I'm happy to release a small project that I've been working on that's very helpful for home lab organization. The Parametric Cable Comb is a tool that allows you to create a cable comb for hanging/storing cables to your specifications. All you need is a 3D printer and some filament. Once you set the parameters in the Thingiverse Customizer tool (alternately you can download the .scad file from GitHub and use the OpenSCAD Customizer), you can then export a custom STL file that can than be processed using your normal 3D print workflow.

I first learned about these while working at Tektronix, and found them extremely useful. However, they don't seem to be common in hobby electronics, although I understand they are used more often in the musical world. This was my first attempt at making a parametric 3D model and my first serious attempt at learning OpenSCAD. If I may say so, it turned out better than I expected. I hope you also find it useful. As always, if you encounter any problems or have suggestions, please let me know.

Built two panels of Empyrean Alpha today; roughly half of what is needed to complete the Empyrean campaign. Here are both panels after finishing post-reflow visual inspection. Should be able to build the other two panels within a few days, then I'll be able to proceed with test. Hoping to start shipping the remaining orders within a week or so!

In a previous post, I mentioned that I was going to need a new laptop so that I could continue working at the dining room table while my boys did their online school work. After doing some research into the options, we were able to budget for a moderately priced laptop in the midrange. I'm already a fan of the desktop AMD Ryzen CPUs and I had heard that the new Ryzen 4000 series mobile APUs were really good, so that's where I targeted my search.

I ended up settling on the Acer Nitro 5 with the Ryzen 5 4600H CPU and Nvidia RTX 1650 GPU (model AN515-44-R99Q). This rig is categorized as a budget gaming laptop, which is not something I strictly needed of course, but competing general purpose laptops with the same CPU cost about the same price, so I figured I'd get the one with the additional GPU instead of relying upon the APU's built-in graphics so that I could do a bit of gaming with my boys during downtime. The Nitro 5 also has a slot for a 2nd SODIMM (running Ryzen in dual-channel memory mode gives you a lot more performance vs single-channel mode) and has room for a 2nd M.2 drive and a 2.5" SSD if desired.

After about a week of using this laptop, I'm extremely satisfied with the performance. It has 6 cores/12 threads for some major CPU power, and it can run a single core at quite a high frequency for applications that like that. It's very snappy in every day use. Also, the battery life is fantastic and unit keeps cool under normal operating conditions. Even when all of the cores are being used, it gets warm but not unbearably hot. The biggest complaint I've seen in reviews is the display. It's a 60 Hz IPS display with 300 nits of brightness. If I were using this primarily for gaming I might like something nicer, but this display still looks so much better than the one on my previous laptop, which was I think a 720p TN panel. I never even use the display at full brightness anyway, in order to conserve battery power.

Overall a big thumbs up from me. AMD has a real winner in the mobile space with their new APUs. The computing power of this laptop approaches that of my main desktop, which is really impressive. Solid recommend from me.

I recently updated my GitHub profile and I'm putting a copy here for reference, since I doubt too many will see it there.

Hello

Hi, my name is Jason Milldrum and my amateur radio callsign is NT7S. I'm the owner of Etherkit, my business which sells open source electronics and amateur radio products. I open source the hardware, firmware, and software of every product that I develop for sale (and others which I don't sell and only post here for others to use).

If you enjoy my released work, take advantage of it, or just like what I'm doing in general, you can help me by subscribing to my SubscribeStar account. At this point, Etherkit makes enough to keep itself afloat and occasionally funds a new bit of lab gear, but that's about it. Purchasing my products through Etherkit or giving further assistance via SubscribeStar helps me to fund the development of new open source products and software/firmware libraries. I believe in Elmering and giving back to the community when I can, and I definitely plan to do more in this area in the future.

As of September 2020, here's what I'm working on and what is coming soon: - I'm completing my Empyrean campaign on Indiegogo and will be moving it to regular production soon. - Next up I will be finishing work on my amateur radio MEPT (Manned Experimental Propagation Transmitter) named OpenBeacon 2. - Working through the large backlog of issues here on my GitHub repos. I have seen them and I'm not ignoring them, I have had to prioritize other things first. - Smaller projects that are mostly completed, such as a Si5351B/Si5351C breakout board, QRP antenna trap board, and some various boards useful for the workbench. - I definitely want to get back to the development of a QRP transceiver for amateur radio use, much like I almost did with my CC1 project. - I'm also interested in make some easy kits for kids to make, as I have a couple of them in my own home! - Would like to put some more work into the Test and Measurement document that I'm collaborating on with LA3PNA. - How to help get new folks interested in ham radio homebrewing is something I'm also mulling over.

This post will be a little more personal than the usual one, but it does involve Etherkit indirectly, so I needed to vent about it.

As you may have seen in previous posts, earlier this year, during the beginning of the lock down, I used my time to complete a big project I was eager to finish: a new office/ham shack for me. We live in a modestly sized house and our boys needed their own rooms, so my office needed to move. The new office turned out just the way I was hoping, but I haven't been able to use it as much because my boys have been home from school since March.

It now turns out that the Beaverton School District won't be holding any kind of in-person school until November at the earliest. The problem with that for me is that the slap-dash online schooling that the boys received at the end of last year was pretty abysmal, and I haven't seen one shred of evidence this summer that shows that Beaverton SD will implement a better system. Since I don't want my kids to fall behind in their education, we decided to enroll them in an online school this year. We made this choice because if they are forced to attend online school, I'd like them to use a system that is proven to work and has been in use for a while. We also got a couple of positive referrals to this school from acquaintances.

What this means for Etherkit is that I'll be out of the office most of the day, and I will be inside, at the dining room table with my boys as they do school on their Chromebooks. The good news is that enough of my work can be done just on a laptop that I think it won't slow me down too much, as long as I invest in a new laptop soon (currently have a 4th gen Intel i3). So even though I'm a bit bummed that I won't have as much time at the workbench, I believe that it won't slow me down too much. The Empyrean campaign should still be on schedule, as of how things are going right now. We all have to adjust to the current conditions. It's not fun, but I'm grateful that our family hasn't been impacted as badly as a lot of others have, even if it has been a frustrating time.

Thanks for listening and for your continued support!

Two days ago, my GPSDO (which I rely upon in the lab as my 10 MHz reference so that I can do accurate Si5351A calibrations, upon other things) stopped acquiring GPS lock. Nothing significant happened in the lab that I was aware of, so I wasn't sure what the issue was. I was just hoping it wasn't a problem with the GPSDO itself. Fortunately a little bit of troubleshooting allowed me to determine that the coax cable from the antenna mounted on the exterior of the shack to the GPSDO had developed a fault. I shouldn't be too surprised by this, as I was using an old bit of RG8X that I've had seemingly forever. I'm lucky to have Ham Radio Outlet in the area, so one phone call and a bit of a drive later, and I had a new length of LMR400 to use as a replacement. The RG8X gave marginal performance, so upgrading to LMR400 was definitely worth it, as I now have even stronger signal levels than before. It's a good reminder that everything degrades, and you can get bitten by entropy at any time.

Regarding the Empyrean campaign, I'm currently in the process of creating a panelized version of the PCB and sending out for quotes. The components to populate the PCBs are now all on-hand. My goal is to send out the panelized PCB for manufacturing within a week. While I'm waiting on those to arrive, I'll be working on the design of the Empyrean test jig. I already have some toggle clamps for the jig and a rough idea of how I want to execute it. Stay tuned for further updates!

I'm building and testing my first batch of Si5351A Breakout Boards in Shack 2.0. Took a bit of work to get my Python test script converted from running on my previous Linux Mint box to now running on a Raspberry Pi 3B+, but now it's working like a charm.

Have been preparing the Indiegogo campaign for the launch of the Empyrean microcontroller. A bit of bad timing on my part, unfortunately. Going to let it simmer for a month or so while I wait to see how the Chinese supply chain is looking. I feel like it would be irresponsible do a campaign ask with this much uncertainty. Watch this space for further updates.

In the mean time, I'm going to work on finishing out my new home office/shack that has been in the works for 9 months now. I'm finishing the interior now, so the end is in sight.

Building with my new manual pick-and-place setup. I'm liking it so far, it's definitely more efficient than my old system of picking up scattered SMT components with tweezers. I'm sure there are a bit more gains to be had by more getting more practice in.

In getting ready for a couple of upcoming product launches, I happened to stumble upon a neat cinematic turntable project on Thingiverse that looked perfect for taking some glamour shots of the new items. I ordered all of the various parts from US vendors on eBay and got to printing the various parts while I waited for the parts to arrive.

I finally received the last of the components needed a few days ago (and had finished printing the printable parts a few days before that), so I was able to assemble and wire up the turntable yesterday. I'm happy to report even though the wiring is a bit of a tangle, it all works well and should make for some nifty video! What a boon it is to have all of these tools at our fingertips these days!

The first of the OpenBeacon 2 pre-production units has been tested and is out to door to its new owner so that it can be on the air for the big QRSS night on New Year's Eve. More will be sent out to testers early next year, and the funding campaign will also be following soon. Watch this space for further updates!

In looking ahead to my next project, I'm starting to learn the new things I'm going to need to know. In this case, I want to do some DSP on audio through a microcontroller. So I've created a Jupyter notebook of a Python implementation of the FIR filter presented in this Hackaday article. Wasn't too difficult to translate from the spreadsheet in that article to Python code, once I got a handle on how the actual filter algorithm worked (which the article wasn't super clear on).

For fun, I think I'll actually play the waveform through the speakers in a Python sketch and then start porting the code over to the Empyrean microcontroller. Will be interesting to learn the limits of the ATSAMD21 in doing audio DSP.

Details about the multiband trap vertical antenna for use with OpenBeacon 2. Currently laying out PCBs for the traps. Once those are done and I've received them from fabrication, will make this post public to ask for testers.

This week I've been working on an antenna that can be used with OpenBeacon2 on multiple bands without the need for an antenna tuner. After a few failed attempts, I settled on an antenna which seems to work well and fit the bill. It is a trap vertical for 40 m, 30 m, 20 m, and 17 m, with elevated quarter wave counterpoises for each band. There's a bifilar 1:1 transformer in the center support of the antenna.

I have been running OpenBeacon 2 on it transmitting WSPR on each of those four bands in succession on random frequencies within the WSPR sub-band. The antenna seems to be working fairly well, as I've been getting spots on all bands (although 17 meters is sparse, I assume because of the lack of sunspots and lack of listeners).

There's a decent chance I'll make PCBs for the band traps and offer them for sale, along with the plans. If you might be interested in testing such an antenna, shoot me an email/message.

I've published my QRP antenna components for 3D printing on Thingiverse and I also have the FreeCAD files on a GitHub repo. I'll probably do a little more refinement on them, but they are perfectly usable as they are now.