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Ham Radio Performance Debug with Datasette

 Had I set the power amplifying transistor's bias high enough, or did the radio always work this way with the amp? It's good to have data!  I've been collecting reverse beacon spots and QSO data since around the start of this year . The reverse beacon data is collected automatically, inspired by a productivity and documentation talk by Simon Willison. Last night, rain got into the Project Toucans radio. It's not waterproof enough yet, I guess. Turns out there are whole issues in using Tuna and fruit cans as radio cases that I'd never thought through. The lid is corrugated making it difficult to seal holes against water. Anyway... Earlier this evening, I had the radio/amplifier combination back up and running, but were they running well enough? Fortunately I had data for that. I queried the data using datasette . I asked about reverse beacon spots since the amplifier was added into the station mix a few days back: select rowid, id, tx_lng, tx_lat, rx_lng, rx_lat,
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Things I Learned: Human Thumbs Look Like Capacitors to Low Level High Frequency RF

 OK, so this isn't so much one I learned, as one I remembered, and then empirically proved. Did you know that human thumbs are capacitative—as in they act like capacitors? Yup! They are! The project TouCans Rockmite/ TunaTopper stack suffers from the same issue the Flying Rockmite often did. Sometimes, the RFI from the antenna gets to be too much, and the memory keyer decides to stop keying out its memory. I noticed that when using the keyer with Project TouCans, if I put my thumb across the leads to the 'dah' keyer switch, the issue went away and the memory keyer ditted and dahed along to completion. I had brought a small capacitor out to the radio site to try placing across the headphone leads to solve an AM pickup problem inherent with having 25 foot long headphone wires. The same issue on a far lesser scale had been solved by Mark— N6MTS —as part of his work on the Open Headset Interconnect Standard, OHIS . The cap hadn't down the job for the Flying Rockmite or Pr

Things I Learned: Using Datasette to search for Ham Radio QSOs in a Date Range

 I've been doing a lot of amplifier testing over the last week with the Tuna Topper as part of what has become Project TouCans. It's led to many more QSOs—meaning, more than one per week—from the house. I maybe haven't remembered to log them all, and so I wasn't too surprised when I saw that  N2AKJ had logged a Parks on the Air, ( POTA ), contact with me last Thursday when they activated K-2114 Nissequogue River State Park . Still, since I didn't remember the QSO, I wanted to make sure I was at least on the air. And.... There's an app for that! Using the RBN network data automatically accumulated by rm-rbn-history about QSOs and RBN spots from my callsign—KD0FNR— served through datasette , I was able to determine if I'd been on the air when the QSO was logged. Spoiler alert: I was. Understanding the SQL formatting to get the information was a bit tricky, so I'm documenting the SQL statement here so I can go back to it later. select rowid, id, tx_lng,

Project Toucans Keyer Design

Project TouCans is well underway! I'll have more details soon. The key difference between TouCans and the Flying Rockmite is that it includes a Tuna Topper amplifier. The amplifier/radio combo chews through the 8 AA batteries more quickly than the Rockmite alone did. Consequently, Diaze—the 12 year old here—and I switched over to D cell batteries. Our keyer, however, is located on a AA battery case. Today, the design for the TouCans keyer became obvious when I looked at the Rockmite's current keyer next to the new battery pack: The two D cell battery packs will be glued together back-to-back. As you can see, the battery pack manufacture graciously included an indentation in the top of the battery packs that holds the on/off switch snugly—even more so after a drop of superglue is applied. The keyer video game switches will be attached in the same way they were on the AA battery pack in roughly the same location at the front of the D cell battery packs. The Ethernet breakout boar

The Morning of Hitting the Zone with Datasette

I'm starting to be handy enough with Datasette that I can quickly get answers to my questions! This morning, the question is whether or not the Tuna Topper amplifier combined with the Rockmite is giving better propagation results than the we get with the Rockmite running alone. Since we have a database of all the QSOs and RBN spots of the Rockmite, this is exactly the kind of question Datasette can answer. Here are the commands to run datasette to get an sqlite database from the Rockmite's RBN and QSO data table . I'm listing the commands here because I've been to lazy to simply write a script, and thus far I haven't been able to get the whole assmeblelage to work on Windows, meaning I'm working on a github codespace. Codespaces are super-cool, but also—at least for me... so far—completely unable to keep command history around between launches python -m pip install csvs-to-sqlite python -m pip install pandas==1.5.0  csvs-to-sqlite -dt timestamp rm_rnb_history

Things I Learned: Modifying installed Python Packages

While the gang and I were using the Datasette csvs-to-sqlite plugin, we learned something about modifying the code of installed Python packages: how to use pip uninstall to find the package. We new we had issues , and we had begun to figure out how to fix them. What we couldn't figure out is where the actual code we needed to modify lived. We'd used pip to install the plugin, so finally I decided to re-install the plugin, and then watch the installation messages as they flashed by hoping to capture the pertinent directory So, I typed pip uninstall csvs-to-sqlite . pip immediately asked me if I really wanted to uninstall the package at the packages location. Problem solved! The kids and I found the code at that location, made our edits, and tried out our newly modified version of the plugin! References: csvs-to-splite plugin

More about Tuna Topper Shielding aka Tuna Soup

A bit more about shielding the Tuna Topper amplifier with a can of Progresso soup. I tried a shielding experiment here at the home station today, and had great results. There was in fact no reductcion in output power. It's unclear to me if there's a reduction in general noise yet. There are roofers next door, and their propane heaters are laying down a nice, even, low-level ground floor. Here's a detail picture of the shielding: The soup can is opened on one end, the soup has of course been removed, and the can cleaned. The open end i placed over the exposed Tuna Topper circuit board. I thought there would be issues with the RF in and out wires being sandwiched between the two cans, but there are not, (at least for this installation.) I made a contact with AE7CG with the shielding in place. Here's the QSO map: You can see the signal was reaching out fairly far, but no further than Utah. This is an afternoon thing here in San Francisco that I haven't entirely figure