Working RTTY with MMTTY and a Yeasu FT-450D

I recently competed in the CQ WPX RTTY Contest. Well, I say “competed,” but the truth of the matter is that I wasn’t remotely in danger of winning the contest. This was my first time working with RTTY, and I spent much of the contest getting my sea legs and learning how it works.

What is RTTY?

Radioteletype or RTTY, is a digital mode that was first used by the military and newspaper industry in the early 20th century. As practiced by amateur radio operators, it is a frequency shift key (FSK) mode, meaning that the broadcast signal is comprised of a tone that is sent on one of two different frequencies. The lower of the two frequencies represents a binary 0, while the upper of the two frequencies represents a binary 1. By switching back and forth between the two frequencies at an agreed-upon rate, a radio can broadcast a string of binary data that can be decoded by whomever receives it.

The binary string that your radio sends represents text that has been encoded with Baudot code, a system not unlike Morse code that assigns a five bit representation to each character or symbol. The five bit string is padded with one start bit and two stop bits, which means that in practice, each character is transmitted as an 8 bit byte.

When first invented, a teletype system consisted of three parts: a teleprinter that displayed the messages received by the system, a modem capable of translating text to code and back, and a radio that transmitted code and received code that was transmitted by another party. In modern amateur radio setups, a computer typically acts as both the teletype and the modem, and is connected to a radio via CAT control and/or an audio interface.

Connecting the Radio to the Computer

The Yeasu FT-450D features a six pin mini din port on its back panel that is referred to as the DATA jack. Readers of a certain age will recognize this type of connector as a PS/2 mouse/keyboard jack.

This image from the FT-450D’s manual shows the pinout of the DATA jack

This DATA jack exposes pins that allow external hardware to control the radio for Audio Frequency Shift Key (AFSK) or Frequency Shift Key (FSK) operations.

To connect my computer to this port, I purchased a cable that breaks the GND, DATA IN, and DATA OUT pins out to a pair of 3.5mm audio jacks. The output jack is connected to the input of a USB sound card, and the input jack is connected to the output of the same.

My USB soundcard, a Focusrite Scarlett 2i2, connected to my Yeasu FT-450D by way of the DATA jack

It should be noted that it’s possible to build your own data cable for this radio. I opted to purchase mine, but plans are available for making a similar cable, as well as a more advanced version that can be used for other digital modes.

Configuring the FT-450D

In order to send and receive RTTY via AFSK, you’ll need to tweak a few options on the Yeasu.

Start by pressing one of the BAND buttons until you find the band that you wish to work. The ARRL band plan will tell you where to find RTTY on each. It should be noted that 30m, 17m, and 12m are called WARC bands and cannot be used for contesting.

With your band selected, press one of the MODE buttons repeatedly until the DATA indicator appears on the front panel.

Next, we’re going to dive into some of the options in the F menu. Press and hold the F key until the MENU indicator appears on the front panel, and then turn the DSP/SEL knob to find each option. Press the DSP/SEL knob to select the option, and then spin the knob to change the value of that setting. One final press of the DSP/SEL knob will save your changes. Once finished, press and hold the F key until the MENU indicator disappears.

The following need to be adjusted for each band that you wish to work:

  • D TYPE: Change this to USER-L, which will cause your radio to receive and transmit data on the lower sideband.
  • DIG VOX: When using AFSK, the radio will automatically begin transmitting when the input audio level exceeds some threshold. The DIG VOX setting adjusts that threshold. Set the output volume on your computer to a reasonable level, start transmitting a RTTY signal, and then increase the DIG VOX value from zero until the radio starts transmitting. When you stop sending the RTTY signal from your computer, the radio should stop transmitting.
  • RTYRPOL: This is the polarity of your RTTY signal (i.e. if the lower pitched tone is considered to be a 0 or a 1). You’ll want to set this option to NOR.
  • RFPOWER: RTTY is more like SSB than other digital modes. When contesting, you’ll likely want to dial your RFPOWER up to 100 if you want to be heard through the pileups.
  • DIALSTP: This one is optional, but because digital modes take up less bandwidth than phone, you may find it useful to adjust the rate at which the tuning knob changes frequencies.

You can find more information about these and other settings in the Yeasu FT-450D manual (PDF).

Installing MMTTY

For my first time out, I chose to use a program called MMTTY as my terminal emulator. CQ WPX RTTY is a contest, and I use N1MM+ as my contest logger. N1MM+ knows how to talk to MMTTY, which should have meant that I would be able to work the contest in a familiar environment similar to the one that I use for SSB contests.

MMTTY trying to decode a portion of the 40m band. Some digital signals are visible on the waterfall in the top right corner, but they don’t appear to be RTTY

In practice, I was late getting started with the contest, and never did figure out how to integrate N1MM+ and MMTTY. Instead, I opted to log manually, which worked well enough for my first time out.

If you opt to use AFSK and connect your radio to a sound card like I did, you will need to configure MMTTY to use the correct piece of hardware. To do this, select Option > Setup MMTTY, and navigate to the SoundCard tab in the window that appears. Use the radio buttons on this page to select the appropriate hardware for input and output.

I configure MMTTY to use my Focusrite USB (the Scarlett 2i2 pictured above) for both input and output

One started, MMTTY will attempt to make sense of whatever white noise it hears on the portion of the band that you’re tuned to.

Sweep through the band while keeping an eye on the waterfall display in the top right corner of the window. You’re looking for two peaks in the audio signal that are the same distance apart as the two vertical yellow lines. If you line the peaks up with the yellow lines, MMTTY will be able to decode the signal, and you should start to see legible text appearing in the big text box in the centre of the window.

To transmit, type a message in the lower text box and then hit your F9 key, or press the red TX button in the upper left hand of the window. The transmit button is not a toggle, so you’ll have to click it a second time (or hit F9 again) to stop transmitting once your message has been sent.

Finally, if at any time you see the word “Overflow” in the top right corner of the waterfall display, that’s an indication that the audio signal from your radio is too loud. Turn down the input volume on either your external sound card, or in the Windows sound panel until the message disappears.

What’s Next?

This coming weekend, the North American QSO Party RTTY contest (PDF) is taking place from 1800 UTC on February 27 to 0600 UTC on February 28. I intend to use this contest as an excuse to either properly integrate N1MM+ with MMTTY, or to try decoding RTTY with fldigi. Maybe both.

Going forward, I’m hoping to use my newfound skills to play with other digital modes. I may even try to contribute some code to one of the many open source projects that are maintained by hams who play on this part of the band plan.

Until then, 73.

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Building the Lego James Bond Aston Martin DB5

For a few years now, I’ve been in the habit of buying myself a Lego set to build over the Christmas holidays. Most years, I pick up a Technic set, but this year, I decided to purchase the Lego James Bond Aston Martin DB5 set, item #10262.

I recently finished building the model, and was very impressed with it. This is the first traditional Lego set that I’ve built in quite some time, so I have surprisingly little experience with models like this, given that I have a large Lego collection.

I was particularly interested in the building techniques that the designers used to model all of the curves and angles on this vehicle. Throughout the build, I was thinking about how designing a set like this must be a constant negotiation between the scale of different parts. Not only does the scale of the finished vehicle have to make sense relative to the diameter of the tires, but the curves on the hood need to be appropriate relative to the overall size of the model, and there are a limited number of Lego pieces to choose from when making those decisions.

As an infrequent builder of traditional Lego sets, I was also really impressed with the construction of the set. Even elements like the vehicle’s doors that you would think are straightforward to build are actually constructed from dozens of small pieces arranged in a really clever manner to achieve the shape that’s required.

The angles that make up the dashboard, windscreen, and trunk of the vehicle are all established by connecting clips and handles together at an angle that isn’t typical to Lego. This means that many of the bricks that make up these parts are at strange angles to the body of the car, instead of everything being built parallel to the ground.

Building techniques aside, I really enjoyed building this set as a James Bond fan. A couple of years ago, my wife and I watched every Bond film in chronological order, and the Aston Martin DB5 is a vehicle that features heavily in canon. True to the films, this model has a number of sneaky spy car features, including a working ejector seat.

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Building a Crib for my Son

When my wife and I started trying to get pregnant, I began designing a crib for my child to be. My rationale was simple: my wife would be providing everything that our child needed over the course of the pregnancy, and aside from caring for her, there wasn’t much that I could do to help the process along. The crib was a project that would keep me occupied, and would provide the child with a safe place to sleep throughout the early stages of its life.

I set about designing the piece in Fusion 360, referencing two YouTube videos for inspiration and checking my work against the Canadian regulations regarding crib design.

I sized everything around a mattress that we purchased from Toys R’ Us. After modelling its dimensions in Fusion 360, I could build the rest of the piece around it.

The design that I came up with was a simple affair with pleasant curves and clean lines:

A render of the 3D model that I built in Fusion 360 before starting the project

Once happy with the design, it was time to purchase the rough stock that I would mill down into the individual pieces that make up the finished crib. I chose red oak for the skeleton of the crib and poplar for the parts that would be painted white.

The rough cut stock for the project, stacked up in my shop before milling began

The Headboard and Foot Board

Each end of the crib is composed of an oak frame that surrounds a floating poplar panel. Because the panel isn’t glued into the frame, the boards that make it up are free to shrink and expand with seasonal changes in humidity.

I cut a dado along the centre of each oak piece. The dado stretches the entire length of the shorter pieces that make up the top and bottom of the frame, but on the longer pieces that make up the sides of the frame, the dado is stopped so that you can’t see it from the outside.

The oak pieces that make up the frame of each end of the crib. Shorter top and bottom pieces are on the left, while longer side pieces are on the right.

I cut a tenon that was sized to fit into the dado on the end of each of the shorter pieces. This allowed the top and bottom of each frame to slot into the sides that make up the legs of the crib. With the joinery cut, I used my band saw to cut a gentle curve along the frame tops, and dry fit the pieces to check my work.

One end of the crib dry fit with clamps. The frame is rotated 90 degrees to the left and is sitting on its side. The panels that make up the centre of the piece have not yet been installed.

Next, I began work on the shiplap boards that make up the centre panel of each end of the crib. I made these pieces out of poplar, a cheaper hardwood that takes paint well. Each shiplap board was cut on the table saw in four passes: Two to form the rabbets on each side, followed by two more to add the chamfered edges.

This is a diagram of the end of a single shiplap board. Multiple boards can be laid side by side, with their overlapping pieces interlocking to form a panel.

With the shiplap boards cut, I could slot them into my dry fit frame to make sure that the joinery was nice and snug. I think that the shiplap adds a pleasant detail to the otherwise smooth face of the end of the crib.

Four of the shiplap boards that make up the middle of one end of the crib fit into place

The Sides

With the headboard and foot board complete, I turned my attention to the sides of the crib. Each side was comprised of two long horizontal oak stretchers spanned by 13 vertical poplar bars. I cut a tenon on the end of each bar, and a corresponding mortise into each stretcher. Since there’s no such thing as a square drill bit, I used a chisel to square up each of the 52 holes.

I lost track of the hours that I spent cutting all of the joinery for the long sides of the crib. While they were certainly less complicated than the ends, the joinery was far more time consuming.
One side of the crib dry fit together after all of the chiselling was completed

The Mattress Support

The final component of the build was the platform that supports the mattress. It’s a simple oak frame with a 3/4″ slab of MDF that sits inside of it.

This frame is really heavy. It turns out that Medium Density Fibreboard is super dense stuff. I’d hate to have to move a sheet of 3/4″ High Density Fibreboard!

My wife and I wanted the crib to be adjustable, with a high position that would be used until our child could sit up, and a low position that would be used thereafter.

When I built the mattress support frame, I opted to strengthen the joinery with wood screws, thinking that they would be hidden by the bottom stretcher of each side of the crib when it was assembled. Unfortunately, I neglected to think about where the frame would sit when in the high position, leaving the screws visible in the final build. Ideally, I would have built the frame the other way round, with the short ends overlapping the long ones so that the screws would always be hidden regardless of the height of the frame.

Dry Fitting the Pieces

To affix all of the pieces of the crib to one another, I opted to use threaded brass inserts and countersunk brass screws. This construction means that I can take the entire crib to pieces with nothing but a large flat head screwdriver, making it relatively easy to transport and to store once our child has outgrown it.

In a previous post, I wrote about the technique that I learned for driving the threaded brass inserts home. Even after I figured that out, accurately positioning the inserts so that they lined up with the holes that I drilled in the corresponding piece remained a huge challenge. I spent a lot of time locating and tuning these holes so that everything would line up at assembly time.

The first assembly of the crib with fasteners in place. None of the pieces have been glued together just yet, so the clamps are holding the headboard and foot board together.

While building the crib, I was also renovating the room that would become our child’s nursery. This turned out to be an equally big job that deserves its own post. Suffice it to say that I bit off more than I could chew, and didn’t manage to get all of the major components of the crib dry fit together until the day before our son was born. Thankfully, friends of ours gave us a bassinet that he slept in until I was able to finish the project.

Finish and Paint

Because of the way that the naturally finished oak and the painted poplar pieces were arranged in this build, I opted to wait until finishing was complete before gluing and of the parts together.

I used my trim router to add a 1/8″ round over to all of the parts that little fingers might be able to touch, and then sanded all of the pieces to 220 grit. Next, all of the poplar pieces were laid out on sawhorses and painted white.

The bars of the crib between coats from a rattle can

My goal was to end up with a smooth paint job, reminiscent of something that you might buy commercially. I started off using spray paint, repeatedly applying thin coats and lightly sanding between each. Although this technique worked, it seemed quite wasteful, so I switched to brushing paint on when it came time to do the shiplap. I still tried to keep my coats thin and sanded between each. Ultimately, I ended up with a smooth, almost plastic finish on all of the white painted pieces.

Once the white paint was dry, I glued everything together, and then set about finishing the oak. For this project, I opted to try Osmo Polyx-Oil satin finish. I started out applying it with a paint brush, but wasn’t happy with the number of drips and sags that I was getting, so I switched to applying it with a rag, rubbing it into the wood in the same way that you might apply furniture wax. This ensured a smooth, even coat, and left the oak feeling natural to the touch.

The two long sides of the crib with a wet coat of Osmo Polyx-Oil on the oak stretchers

Installation

By the time the crib was finally ready to be moved into our son’s room, it was the first week of November, nearly two and a half months after he was born.

Assembling the crib in my son’s nursery

Thanks to the threaded inserts and brass screws, installation was a snap. The finished crib is really heavy, and requires two people to move, so it’s a good thing that it can be easily taken to pieces.

The finished piece looks great in the corner of my son’s room. It’s far and away the nicest piece of furniture that I’ve built to date, and the fact that it was built with love for my son makes it all that much better.

Our boy trying out his new bed for the very first time ❤️

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Photo Organization Part 1: Importing Existing Files

Over the years, my wife and I have accumulated a large volume of digital photos. Nary a vacation has gone by that didn’t result in 1000+ photos of every landmark, vista, and museum artifact that we discovered during our travels.

As it turns out, the Continental Hotel from John Wick is actually a sushi bar

Unfortunately, the majority of these photos have ended up haphazardly organized in various folders on my media server, all with different directory structures and naming methodologies, which makes it difficult to lay my hands on a particular photo from some time in the past.

One of the projects that I’ve decided to tackle this year is to come up with some method by which to rein in this madness and restore some semblance of order to the realm.

I’m not sure exactly what tools or processes I will use to tackle this problem, but I figure that the best way to start is to split it up into smaller, more manageable sub-problems.

This, then, is the first in what I hope to be a series of posts about organizing my family photo collection. Subsequent posts will (hopefully) deal with a pipeline for importing new photos, establishing a reliable offsite backup solution, and maybe even experimenting with some deep learning to automatically tag photos that contain recognizable faces.

Why not use [Insert Cloud Service Here]?

“But,” I hear you protest in an exasperated tone of voice, “you could just upload all of your photos to Google Photos and let The Cloud solve this problem for you.”

While it’s true that there are a number of cloud providers that offer reasonably-priced storage solutions, and that some of them even use the metadata in your photos to impose some kind of organization solution, I have a few concerns with these products:

  1. They cost money: Nothing in life is free, at least not if you have more than a few gigabytes of it. The largest of my photo folders contains around 70GB of files, and with the recent arrival of our son, we take new photos at a heretofore unimaginable clip. I already have a media server, and storage on it is effectively free.
  2. My metadata isn’t complete/correct: Garbage in, garbage out, as they say. Most (all?) of the cloud storage solutions that I’ve seen that purport to organize your photos will do a messy job of the task if the metadata on your photos is incorrect or missing. Any tool that I use will need to correct for this problem.
  3. Google is a creep: The same is true of Facebook et al. I’d rather generate less digital data for the multinational companies that control our modern world to indiscriminately slurp up and process in hopes of getting me to click on a single ad, thank you very much. Doubly so if the storage provider in question is going to use facial recognition to tie a name to faces in my photos, especially photos of my son.

Organizing Files with Elodie

My initial inclination, when considering the problem of sorting many gigabytes of photos into a reasonably logical folder structure was to write a script that would read the EXIF data out of the file, interpret it, and use it to determine where the file belongs.

But the decrepit fire station from Ghostbusters? Actually a fire station.

In one of the better decisions that I’ve made so far this year (hey, it’s only January), I decided to take a look around GitHub to see if somebody had already written a script to do this work, and man, am I glad that I did.

As with most things that seem simple, it turns out that the task of reading EXIF data can get really complicated in a hurry. There are a bunch of different historical format differences, every camera manufacturer implements some number of custom extensions to the format, etc.

Enter Elodie

Elodie is a cutely-named tool with an even cuter mascot that uses exiftool to read the metadata out of your photos, and then sorts them into a configurable folder structure based on that data. If your camera or phone wrote GPS coordinates indicating where the photo was taken, Elodie can even query the MapQuest API to translate those coordinates into a human-readable place name that is added to the directory structure.

The documentation is comprehensive, albeit brief, but I’ll include a handful of the commands that I used in this post just to demonstrate the workflow that I ended up with.

There are basically two major operations in Elodie: import and update. The former is used to move pictures from some source directory into the target directory, reading their metadata, renaming them, and organizing them within a configurable directory structure along the way. The latter, meanwhile, is essentially used to correct mistakes that were made during the import process. It lets you correct the date, location, or album metadata for previously imported files, and appropriately re-sorts them into the directory hierarchy.

The command for importing existing files into your collection is simple:

~/elodie $ ./elodie.py import --trash --album-from-folder --destination=/mnt/media/Pictures/ /mnt/media/Pictures.old/Montreal\  Trip/

In this case, I’m importing vacation photos from /mnt/media/Pictures.old/Montreal Trip. The destination folder is /mnt/media/Pictures, and I’m using the --album-from-folder option to tell Elodie that I want it to keep all of the pictures in this batch together in a folder called Montreal Trip in the destination directory. We went on this trip in September of 2010, so the resulting folder structure looks like this:

mnt/
├─ media/
│  ├─ Pictures/
│  │  ├─ 2010/
│  │  │  ├─ September/
│  │  │  │  ├─ Montreal Trip/
│  │  │  │  │  ├─ 2010-09-08_19-29-44-dsc00279.jpg
│  │  │  │  │  ├─ 2010-09-09_20-15-44-dsc00346.jpg
│  │  │  │  │  ├─ ...

There may be other pictures that were taken in September of 2010 in the September folder, but they won’t be sorted into the Montreal Trip folder unless they are marked as being a part of the Montreal Trip album.

It should be noted at this point that Elodie goes to great lengths to avoid maintaining a database of imported files. Instead, it reads metadata from and writes metadata to the image files that it is organizing. This ensures that the resulting directory structure is as cross-platform and broadly compatible as possible without locking your photo collection into a proprietary file format.

The Men in Black Headquarters at 504 Battery Drive

Elodie does offer one database-lite feature that helps to detect bit rot: The generate-db operation records a cryptographic hash of every photo in your collection into a file. Months or years down the road, you can check if any of the files in your collection have become corrupted by running the verify operation. This will recompute the hashes of all of the files in your collection, compare them against the previously recorded values, and let you know if anything has changed.

One place where not having a database falls short is if a small handful of images within a directory that contains hundreds or thousands of vacation photos have incorrect or missing EXIF data. In this case, it’s possible for those photos to be written to the wrong place in the target directory structure, and if you don’t catch the problem during the import, you’re not likely to find and fix the mistake. If Elodie were to maintain a database that tracked the source and destination locations for every imported photo, these mistakes would be easy to find. This in turn means that importing a large existing photo collection with Elodie becomes a job that requires human supervision.

Here’s a brief rundown of some of the issues that I ran into while importing a large collection of existing files:

  • Missing metadata: Some photos, particularly those taken by pre-smartphone cameras, didn’t have the date on which the photo was taken in their EXIF data. When it encounters this problem, Elodie falls back to the lesser of the file created or file updated date. Because of the way that I managed my import, all of these files ended up in Pictures/2021/January/Unknown Location/, but if you didn’t accidentally overwrite the file created date on all of your photos as a part of your import process, Elodie may put them into an unexpected location in your target directory tree.

    If you happen to be importing an album (i.e. a bunch of photos that were taken as a part of a named event) and your target directory structure includes the album name, you can find the improperly organized photos by running find /path/to/photos -type d "album name" -print to find directories in your collection that have the same name as the album. Once found, you can use Elodie’s update operation to fix the problem:
    ~/elodie $ ./elodie.py /update --time="2014-10-22" --album="album name" /path/to/photos
  • Incorrect metadata: In many ways, incorrect metadata is worse than missing metadata, because it causes photos to be organized into unexpected locations. As far as I can tell, the cause of this problem was a pre-smartphone camera that had its date and time set incorrectly. Remember when you used to have to set the date and time on all of your electronics? Boy, that sucked.

    You’ll know this is the problem if you are importing photos from a vacation that you took in 2012, but they’re inexplicably being put into the 2008 directory. In this case, you can use exiftool, the underlying library that Elodie uses to read and write metadata, to add or subtract some number of years, months, days, or hours to or from the dates recorded in the photos’ EXIF data.
  • Geotag lookup doesn’t appear to work: As mentioned above, Elodie has the ability to convert GPS coordinates found in the EXIF data of photos into human-readable place names by way of a call to the MapQuest API. This, of course, only works if your camera was aware of its location at the time that the photo was taken, which wasn’t really a thing in the pre-smartphone era.

    This isn’t really a problem for vacations, as I can import all photos from a trip into an album, and that album name will be used in the folder structure that Elodie creates. For example, if you import photos from a folder called Egypt using the --album-from-folder option, they’ll end up in a directory structure like this: 2012/March/Egypt/.

    It does, however, get annoying for photos that were taken closer to home with a non-GPS-aware camera. These all get sorted into a year/month/Unknown Location/ directory. I can’t find anything in the Elodie docs or source code that allows this behaviour to be changed. I would rather that these photos end up in the root of the year/month/ folder, because I think that the extra Unknown Location directory is, well, less than helpful, but I recognize that this is a matter of preference. For now, I think I’ll solve this problem by writing a quick script to move these photos as I see fit.

What’s next?

Even with the help of a tool like Elodie, reorganizing tens of gigabytes worth of photos is not a quick task. I can hear the fans on my Drobo humming, and am only too aware that this kind of mass file migration is a great way to find the breaking point of old hard drives.

This isn’t from a movie. It’s just a cool shot looking North from the top of the Freedom Tower

Once I’m done importing all of the pictures that I already have, I’ll move on to figuring out an import pipeline for photos that I haven’t yet taken. Off the top of my head, it needs to be mostly automatic, work well with the iPhones that my wife and I use to take most photos these days, and should ideally email me the Elodie log so that I can see what photos ended up where and whether or not I need to manually correct any mistakes.

I’m hopeful that once I get around to importing photos that were taken with a smartphone that has internet time and some notion of its location, the metadata problems that I catalogued above will become the exception instead of the rule.

Once I figure out that next step, I’ll write about it here. In the meantime, go organize all of those photos that are cluttering up your media server. You’ll feel better once you do. I promise.

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How to Install Brass Threaded Inserts

I’m currently working on building a crib for my firstborn son. There are two elements of this design that make it unique among the furniture that I’ve created in the past:

  1. The mattress should have two distinct heights: an upper height for when he is an infant, and a lower height for when he is a toddler
  2. I need to be able to disassemble the piece; both to move it into the nursery, and for storage once my son has outgrown it

I opted to solve both of these problems by building the crib out of five flat pieces that are affixed to one another using 3/8” brass screws and threaded inserts. I chose brass here for its aesthetics, thinking that the brightness of the brass would play nicely against the warmth of the wood.

The product that I chose for this purpose was E-Z Lok 3/8”-16 threaded brass inserts:

The kit comes with some the threaded inserts, and appropriately sized drill bit, and a slot head driver that is supposed to allow you to drive the threaded inserts home using a drill. Separately, I purchased some slot head brass screws that thread into these inserts from McMaster Carr.

When choosing these fasteners, I made the mistake of assuming that both the screws and threaded inserts needed to be made out of brass brass.

In practice, the threaded inserts are never visible when the crib is assembled, so I could easily have used a threaded insert that was made out of steel, which would have handily avoided all of the problems that I encountered when trying to drive the relatively soft brass inserts into the hard oak of the crib body.

On the right, a virgin threaded insert. To the left, a threaded insert that was destroyed when I tried to drive it into the end grain of a piece of oak using the tool included in the kit

After a few of the brass inserts tore themselves to pieces during my early testing (which I thankfully conducted on scrap, and not on my finished piece), I turned to Reddit to ask the community of r/woodworking for help installing these fasteners.

The solution came from user u/okacookie who suggested that I thread a nut most of the way onto a 3/8”-16 hex head bolt, and then thread the bolt into the threaded insert, jamming the threaded insert up against the nut. This way, a hex driver or ratchet can be used to drive the threaded insert into the oak workpiece without having to rely on the flimsy slot head that has a tendency to rip to if you so much as look at it the wrong way. Once the threaded insert has been driven home, the bolt can be backed out, leaving the insert behind.

In practice, I found that starting the threaded insert with the slot driver that was included in the E-Z Lok kit before switching out to the jam nut and ratchet combination worked best for me.

In closing, if you find yourself using these brass threaded inserts, first ask yourself if they absolutely have to be made from brass. If not, use a stronger metal. If so, ditch the silly slot head driver and use a bolt with a jam nut to get the job done.

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CAT Control with N1MM+ and a Yaesu FT-450D

When participating in amateur radio contests, my logging software of choice is N1MM+. This tidy little logger is highly optimized for contesting, automatically updating its user interface to prompt the user for the information required to log a valid contact.

One major quality of life improvement for me has been rigging up N1MM+ to talk to my HF rig via CAT control. This allows the logging software to automatically transmit pre-recorded macros on my behalf at the appropriate times during a contact, which saves me from having to yell my callsign over and over again when trying to break through a pileup.

Because every radio is different, configuring N1MM+ to control your rig can be a bit of a bear. Below are the steps that I followed to get things working:

Tell N1MM+ What Kind of Radio You Have

From the main window of N1MM+, select Configure Ports, Mode Control, Winkey, etc… from the Config menu.

In the Configurer window that appears, activate the Hardware tab. Select the COM port that your radio is attached to from the Port dropdown, and the make and model of your radio from the Radio dropdown.

Next, click on the Set button under the Details header. In the window that pops up, select the baud rate of the serial connection with your radio from the Speed dropdown.

Click the OK button twice to dismiss both windows and navigate back to the main window of N1MM+.

Customize the CAT Commands that N1MM+ Sends to your Radio

From the Config menu, select Change CW/SSB/Digital Function Key Definitions > Change SSB Function Key Definitions. In the SSB Message Editor window that appears, you can edit the contents of the config file that controls the CAT commands that N1MM+ sends to your radio at different stages of the contact.

When running (i.e. sitting on a particular frequency calling CQ and waiting for other operators to call me back), I execute the VM1TX function on my Yaesu FT-450D, which transmits a pre-recorded macro that says something like “CQ Contest CQ Contest, Victor Alpha Three Juliet Foxtrot Zulu”.

To execute this command, I have to configure N1MM+ to execute the {CAT1ASC PB7;} command. CAT1ASC tells N1MM+ to send an ASCII command down the serial connection, and PB7; tells my rig to execute the VM1TX function, which transmits the pre-recorded macro.

Similarly, when searching and pouncing (i.e. tooling around the band looking for other operators who are calling CQ), I execute the VM2TX function on my radio, which transmits a different pre-recorded macro says my callsign. I use this when answering another operator and waiting for them to acknowledge me.

Executing this command is much the same as the previous. I configure N1MM+ to execute the {CAT1ASC PB8;} command, which tells my rig to execute the VM2TX function, transmitting the pre-recorded macro.

For reference, here’s the contents of my entire SSB Message Editor config file:

#
# SSB Function Key File
#
# Edits may be necessary before using this file
# Use Ctrl+O in the program to set the Operator callsign
#
###################
#   RUN Messages
###################
F1 CQ,{CAT1ASC PB7;}
F2 Exch,{OPERATOR}\CqwwExchange.wav
F3 TNX,{OPERATOR}\Thanks.wav
F4 {MYCALL},{CAT1ASC PB7;}
# Add "!" to the F5 message if you are using voicing of callsigns 
F5 His Call,
F6 Spare,
F7 QRZ?,{OPERATOR}\QRZ.wav
F8 Agn?,{OPERATOR}\AllAgain.wav
F9 Zone?,{OPERATOR}\ZoneQuery.wav
F10 Spare,
F11 Spare,
F12 Wipe,{WIPE}
#
###################
#   S&P Messages
###################
# "&" doubled, displays one "&" in the button label
F1 S&&P CQ,{CAT1ASC PB8;}
F2 Exch,{OPERATOR}\S&PExchange.wav
F3 Spare,
F4 {MYCALL},{CAT1ASC PB8;}
# Add "!" to the F5 message if you are using voicing of callsigns 
F5 His Call,
F6 Spare,
F7 Rpt Exch,{OPERATOR}\RepeatExchange.wav
F8 Agn?,{OPERATOR\AllAgain.wav
F9 Zone,{OPERATOR}\RepeatZone.wav
F10 Spare,
F11 Spare,
F12 Wipe,{WIPE}

Note of course that unless you also run a Yaesu FT-450D, lines 10, 13, 28, and 31 will need to be customized to send CAT commands appropriate to your radio.

Reading through the file may also suggest to you that there is more than one way to skin this cat; indeed, it is possible to configure N1MM+ to key your radio and then play a WAV file from your computer, assuming that you pipe the audio from your computer into your rig. This can be a solution for radios that don’t allow you to record voice macros, or for operators who want to use a wider range of macros than their radio supports.

Good luck and happy contesting!

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CAT Control from Log4OM 1.x Using hamlib

In a previous post, I wrote about using hamlib to control my Yeasu FT-450D from the Windows command line.

This time, we’ll look at integrating hamlib with Log4OM to achieve cat control from within the logging software, primarily so that I don’t have to record the frequency whenever I enter a new QSO.

If you haven’t already installed hamlib, you’ll want to follow the instructions in the previous post. If you can run the rigctl examples in that post, you should be good to go.

Configuring Log40M

First, we need to tell Log4OM to use hamlib. Unlike N1MM+, Log4OM does not come with the ability to talk to your radio, and it needs some help to do so.

From the Settings menu in Log4OM, choose Options, and in the dialog box that appears, select the Cat & Cluster tab. We only care about two controls on this tab:

  • Under the CAT SOFTWARE heading, choose hamlib
  • Under the CAT & Cluster heading, select the Open CAT on program start checkbox

Click on the big floppy disk in the bottom right corner to close the dialog box.

Back on the main screen of Log4OM, click on the icon that looks like a pair of headphones in the toolbar:

Why it’s a pair of headphones is beyond me. While I do wear headphones while using my HF radio, they don’t have anything to do with cat control.

Anyway, clicking on that button will open the Log4OM Cat dialog box, where you can configure cat integration with your radio. There are three settings that you want to change in this window:

  • Select the make and model of your rig from the RIG Model dropdown box. My primary HF radio is a Yaesu FT-450D, and I use the Yaesu FT-450 0.22.1 Beta | 127 profile.
  • Select the COM port that your radio is connected to. My radio typically connects to COM4, but that can change if I plug its serial cable into a different USB port
  • Choose the appropriate Baud Rate for your radio. My radio is set to 9600 baud, but this can be changed in its menu. The radio and Log4OM have to be expecting the same Baud Rate for communication to be successful

Once configured, press the Open button in the bottom right hand corner of the dialog box to test and save your settings. if the CAT Status indicator in the bottom left corner of the dialog box turns green, you can close the box.

So What’s the Point?

Once you configure cat control, Log4OM will communicate with your radio as you use it. Most notably, the frequency that your radio is tuned to will appear in the top right-hand corner of the logger, and will automatically record that frequency in any new QSOs that you enter.

Cat control also allows Log4OM to change your radio’s transmit/receive frequency, and to activate the radio’s transmitter. This in turn allows you to connect your radio’s audio input and output to your computer, and play pre-recorded audio snippets from the logger, which can be very useful while contesting.

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Using ImageMagick to Prepare Images for Upload on Windows

A few years ago, I wrote a short post detailing how to automatically rotate, resize, and strip EXIF data from the images that I upload to this website.

At the time, I was working on Linux, so the instructions in that article target Linux-based operating systems. Over the intervening years, I’ve switched back to running Windows 10 on my home laptop, so I figured it was time to update my original instructions to target my new platform of choice.

Installing ImageMagick

One of the reasons that I now run Windows at home (or at least one of the reasons why I don’t mind running Windows at home as much as I once did) is that the Windows command line experience has improved by leaps and bounds over the past few years.

For command line goodness in Windows, I run PowerShell inside of ConEmu, and I use Chocolatey to install and manage command line utilities.

Luckily ImageMagick is available for Windows, and you can install it via Chocolatey as follows:

$ choco install imagemagick.tool

Note that I’m purposefully installing the portable release here, because it includes all of the command line tools in addition to the main ImageMagick GUI application.

The installer modifies your $PATH variable, so you’ll have to run refreshenv once it’s complete.

Modifying Images with Mogrify

As in the original tutorial, I still use mogrify to prepare my images for upload.

Start by copying the images that you want to use into a temporary folder. Mogrify is going to modify them in place, so you definitely don’t want to work against the original images.

Next, run the following command from PowerShell/cmd in the temporary folder:

mogrify -auto-orient -resize 584x438 -strip -quality 85% *.jpg

This command will re-orient and resize your images, strip any EXIF data from them, and re-encode them as jpegs at 85% quality. The full manpage for mogrify can be found on the ImageMagick website.

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Using hamlib to Control my Yeasu FT-450D

A couple of years ago, I became VA3JFZ after studying for and passing my amateur radio exam. Since then, I have been building out my shack (ham radio enthusiast lingo for the place where you keep your rigs, er… radios).

As my setup has matured, I’ve started to look for interesting ways to interconnect my equipment. Most amateur radio operators use software packages called loggers to keep track of who they’ve talked to when on the air. I use two different loggers: log4OM is my everyday driver, and N1MM+ is for contesting.

Some of my recent contacts, or QSOs, as recorded in log4om

While contesting, I got used to N1MM+ automatically reading the frequency from my HF (that’s high frequency) radio, making for one less thing that I have to enter into the logger as I work contacts. While trying to figure out how to get log4om to do the same thing, I stumbled on an open source project called hamlib.

You see, while most modern rigs provide some form of CAT (that’s computer aided transceiver) control via an RS-232 serial port, every manufacturer’s radio responds to a slightly different set of commands. The goal of the hamlib project is to create a common interface that any piece of software can use to talk to all kinds of radios without having to re-implement all of their individual peculiarities.

After downloading the release 3.3 and running the exe file, I added the C:\Users\Jonathan Fritz\AppData\Roaming\LogOM\hamlib directory to my PATH and opened Powershell, where the following command started an interactive terminal:

$ rigctl --m 127 --r COM3 --serial-speed=9600

Let’s break down the arguments to this command:

  • rigctl is the name of the program, pronounced “rig control”
  • --m 127 tells rigctl that my radio is a Yeasu FT-450D
  • --r COM3 says that my radio is connected to the COM3 port; and
  • --serial-speed=9600 tells it that my radio expects serial commands at a rate of 9600 baud.

It’s worth noting that your radio might appear on a different COM port when connected to your computer via a RS232 to USB cable, and that you may need to adjust the baud rate of the serial connection to match the settings in your rig’s config menu.

You can find out what COM port your radio is connected to in Windows > Control Panel > Device Manager

Once you’ve started rigctl, there are a few interesting commands that you can run.

Get the frequency of the radio:

Rig command: f
Frequency: 7301000

Get the mode that the radio is in:

Rig command: m
Mode: LSB
Passband: 3000

Ok, that’s a neat party trick, but what’s the point? Well, rigctl can also be used to change your radio’s settings, and can be run in a non-interactive mode where commands are read in from a file.

Non-interactive mode

I started by writing my commands out to a file:

$ echo M LSB 3000 \r\n F 7150000 > 40m.txt

Once again, let’s break this command down:

  • echo prints whatever comes after it to the terminal
  • M LSB 3000 tells the radio to set the mode to lower sideband with a passband of 3000Hz
  • \r\n is a line break in Windows, which separates two commands from one another
  • F 7150000 tells the radio to set the frequency to 7.150.00MHz, the middle of the 40M band
  • > pipes the output of the echo command (the string M LSB 3000 \r\n F 7150000) into a file on disk
  • 40m.txt is the name of the file to pipe the command into

The result is a file called 40m.txt containing two commands that will set the radio to LSB mode and set the frequency to 7.150.00MHz.

Now, we can execute those two commands by running this command:

$ rigctl --m 127 --r COM3 --serial-speed=9600 - < 40m.txt

The first four arguments here are the same ones that we used to open the interactive terminal above. The remaining arguments are:

  • - tells rigctl to read the remaining commands from stdin, letting us pipe them in from a file
  • < the opposite of >, pipes commands in from a file instead of out to a file
  • 40m.txt the name of the file containing the commands that we want to send to the radio

Running this command will set the radio’s mode and frequency, initializing it for operations on the 40m band.

The rigctl manual contains a bunch of other really interesting commands, including the ability to activate the rig’s PTT (push to talk) switch, which could be used to write a script that puts the radio into transmit mode before playing pre-recorded message. That sounds like a very useful feature for contesting.

Finally, if there’s something that your radio can do that rigctl can’t, you can always use the w command to sent CAT control strings directly to the rig. The control strings for most rigs can be found on the manufacturer’s website.

73 (that’s amateur radio speak for “best regards”), and enjoy your newfound power.

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Classy Walnut Monitor Risers

In this video, I show you how to make some great looking walnut monitor risers that feature continuous grain up one leg, across the top, and down the other leg, as well as hard maple splines that strengthen the miter joints between leg and top.

Monitor risers are a really simple project that anybody can make to add a little class and a personal touch to an otherwise drab workspace. If you make some of your own, please share them in the comments below, or on social media.

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