Copasetic Flow

  I knew I saw a video with 9 volt batteries used for arc welding!  During the ongoing discussion about Agent Sonya , using 9 volt batteries as a vacuum tube plate current power supply came up. I found references to doing such a thing on one of Pete's blog post s. I also vaguely remembered a Jeri Ellsworth video where forty 9-volt batteries were connected in series. (The tops of these batteries makes the operation fascinatingly simple.) I finally found the video today. It is amazing! So! We now have visual evidence that nine volt cells can be put to rather spectacular use!

 Raspberry Pi released the Raspberry Pi Radio Module 2 today. It's the same wireless module supporting both WiFi and Bluetooth that's used for the Pico W and the Pico 2 W, but it's packaged as a standalone module . Photo of Pi Radio Module 2 from release announcment I don't know if we'll wind up using this module on Project TouCans, but the external antenna you can see on the right-hand side of the module abovoe has been enticing at various points during the project. I know that extending the antenna would violate the conformance and RF certification that the module provides, but Project TouCans isn't a commercial product yet anway, so... There are games we can play with just the module itself though. The first of which would be to move from a Pico-W to a Pico and move the processor module inside TouCans, leaving only the wireless module on the ouside of the device.  TouCans Current Setup with Pico-W on the Outside This should make the whole rig more rugged, bu...

 I do a lot of work with maps of the F2 layer of the ionosphere. I found two good articles, (so far), this week that I wanted to pass along. The first has to do with the ionosphere itself and how signals propagate through it. The Department of Commerce book , ( here's the older 1948 version ), on the ionosphere that I frequently quote and more frequently use cites a number of formula and diagrams without a whole lot of explanation. I finally checked out the references this week and found that much of the information I use from that book—including the figure below—comes from this more information-dense paper by Newbern Smith. The second paper hits on the topic of quaternions—one of my perrenial favorites—in  relation to rotations in video games. How did I find it? Using ChatGPT to prototype mapping apps again, of course. I wanted to find what squares on a spherical map of the Earth a QSO path traveled through. ChatGPT suggested susing something called a slerp . Wondering if t...

 N2CQR mentioned the waterfall being handy for QRP in that other operators can find your rock-locked signal on the ham radio bands.  In addition to the use-case pointed out by Bill , when operating Project TouCans in locations where there's an available internet connection, I've used SDR waterfalls to my advantage in a few other ways: 1. I can get more immediate feedback than the Reverse Beacon Network. On the West Coast, the Utah SDR can see our signal during most of the day. We can find out immediately if Project TouCans is working at all. 2. I rarely have zero-beat issues with TouCans. The contained RockMite's receiver is very wide, so I can hear a lot on either side of the frequency the rig works on. There is one big issue though. The crystal oscillator for transmit has found its home near 14057.4 MHz. The receive bandpass, however, is happiest at 14057.9 kHz. Especially when there's a crowd, the waterfall display from Utah helps me to determine if the loudest sign...

 One consideration that I hear often with relation to vacuum tube circuits is to be very, very careful of the high voltages that are typically involved. And, I completely agree. What if the highest voltage was 45 V though? A battery operated rig would seem more useful to Agent Sonya in my opinion. I went searching for something that might take less voltage, and therefore be safer for construction by the gang and I. It didn't take too long to find something that might work as a basic concept, although I do understand that the operating frequency of the circuits shown below wouldn't transmit long distances. Here are the schematics from the 5 meter rig outlined in the March, 1936 issue of Radio Craft  on page 525 Notice that at first glance, the highest voltage involved is from a 45 V battery. The 'interruption-frequency' coil concerns me a bit because I don't know what it's for yet, and it looks like a transformer. Upon further reading, and squinting at the acro...

 ChatGPT wrote a little more starter code for me to answer the question, could we simply make an image of the F2 maps? Here are the current 3D F2 maps . These are great for visualizing what the ionosphere F2 height actually looks like. The maps are, however, a little memory and processor heavy. I wondered if would be faster to load a simple image for a daily driver sort of F2 map. I asked ChatGPT for help, and while things took longer this time, the LLM still made quicker work of the project. Here is one of the early sample outputs. Notice that the map is still split into grids in the same manner as the Cesium map. The only remaining task was either to display a legend on the same web page, or to use tooltips! I chose tooltips. To implement tooltips, I needed an html <map> tag containing the FoF2 values at each grid location with FoF2 image. That wound up being a bit of a journey. My first idea was to simply crank out an entire html page in the GitHub repos and display it he...

 How difficult is it to build a single tube ham transmitter? Honestly, I don't know because I haven't tried. The gang and I are out camping this week and thoroughly enjoyed listening to the latest episode of the Soldersmoke podcast as we were out exploring the area around Baker, NV. In the podcast, (episode 260), Agent Sonya  came up again. (Here's the Soldersmoke blog post for the podcast.) I have to say, I'm still a believer. Maybe it's time to put my money where my mouth is though. So, this week, the kids and I will be researching: The article in the 1936 radio handbook on page 111. Whether or not we can still get our hands on a functioning 6C6 tube and socket. Can we find a crystal that fits into a socket like the ones advertised in the back of the handbook? Can we maybe bring the plate voltage 6A6—aka a 53 tube—down to something more manageable than 450 Volts?  How does the circuit function and how does it depend on plate voltage anyway? What sort of oscilla...

 I was the second person to activate US-9269 Mt. Moriah BLM National Conservation Area yesterday! The gang and I are out on our annual campign trip to Baker, NV and the environs surrounding Great Basin National Park. We drove to our trailhead using the Hatch Rock Mine access road. The mine extracts quartzite for use in building. The entire wilderness area where the gang and I hiked had frequent quartzite deposits.  That second photo shows the top of a quartzite outcropping that wound up being about four stories high when viewed from below. I realized this once I got to the bottom of the outcrop as I descended the ridge I was on after the POTA activation. Google had this to say about the stone: Mt. Moriah Flagstone is a premium metamorphic quartzite sourced from the pristine Snake Mountain Range on the Nevada-Utah border. This exquisite natural stone showcases a harmonious blend of slate gray, soft mauve, and warm tawny chestnut tones, creating an aura of delicate refinem...

 I haven't tried this before, but it was a lot of fun. On this video QSL, I explained what was going on with the rig, (Project TouCans), and the Morse code within the QSO with N4GO in words on the video as the QSO was in progress. New video style for N4GO de KD0FNR The map below is for the entire POTA activation. It shows RBN spots as 'glowing' lines this time and QSOs as solid lines, (like always.) You can click on any of the signal paths to get more inforatmion about it. You can click the play button on the lower lefthand control panel to animate the map so you can see the QSOs as they occurred. QSO/RBN  Map for the 2025-05-20 KD0FNR US-0757 POTA Activation

 We moved to a web based control panel for Project TouCans a few months back. It's worked really well. Changing the network model of the system to one where TouCans uses a smart phone for network resources as a client even unexpectedly reduced the audio noise in the rig. Even though the control of the rig is now done via browser, KO6BTY and I hadn't tried to control the rig from more than one smart phone until our recent US-4578 POTA. Before I go any further, here's a brief introduction to the control panel. On a POTA activation last week, I set up the rig to talk to my smartphone via a mobile hotspot. KO6BTY then set up her smart phone to use my smart phone as as Wi-Fi source. The rig was immediately available to her at the same internet address! TouCans has almost moved into the cloud! For now, it's moved into the WLAN! The control panel doesn't have the concept of multiple users yet, so Hamie and I had to adjust keying speeds when each of us took control over fr...

 I spent a little bit of time doing math debug this weekend, but in the end it turned out the QSO mapping app had a visualization issue, not a math issue. It was fun to get to look at the math for calculating the apparent launch angle of our antenna using F2 height data and rx/tx station locations. I wouldn't have thought to do the review except I had data that didn't match the maps I was getting back. According to the launch ange calculations made by our, (mine and KO6BTY's), QSO mapping app, the launch angle for the signal from our QTH was 0.00227 degrees. The map however, showed the path of the signal soaring over the very nearby Bay Bridge. The angle shown is much larger than 0.00227 degrees. Here's a picture of the nearby Bay Bridge with our antenna in the foreground. After completely reviewing the underlying math, it occurred to me that CZML likes to make lines that follow great circles. To make something that approximated a circle out of a path with a very low ...

 Just a few notes on the varactor that's providing the FSK on the Rockmite and a few more notes on the FSK circut itself. This page will continue to evolve and is related to the slow moving project to try out teletype with Project TouCans . To communicate in most of the 20 meter RTTY band, the rig needs to have a 175 Hz FSK, rather than 500 to 700 Hz. I'm woroking on understanding the FSK circuit to see if it can be modified to give the desired shift. Short conjecture: I suspect/hope I can place a small variable capacitor around the varactor to bring the frequeqncy shift into the range that will work. The RockMite achieves frequency shift with its Colpitts oscilator via the following circuit from the manual and I'm just not sure how this works out. When Q2 closes, it looks like there should be a short to ground. The Zener, D5 with its 4.7 V reverse voltage, is immediately gone. Using the capacitance chart below, it looks like we gor from 100 pF from the varactor ot on the ...

 Can a RockMite send RTTY without a modification? Maybe. There are are two reasons it might not be able to. First, the keyer might not quite work the way I'd like for it to. What I need the keyer to do is to allow me to hold the key down in straight key mode while changing the FSK frequency of the rig by tapping the programming button. The second reason is that the frequency shift on RockMite's is between 500 and 700 Hz. Meanwhile, most rigs on the ham bands use a 45.5 baud rate with a 170 Hz separation. However, the German weather teletypes transmit at 50 baud with a separation fo 500 Hz, so there's a precedent for recievers that could decode RockMite RTTY if a RockMite could RTTY. The nice thing—the thing that got me thinking about teletype at all—is that RockMites have a built in, controllable FSK. Consequently, I asked ChatGPT to write microPython code to pull the FSK line on the RockMite. What I hadn't thought through was that KO6BTY, or I still needed to add a re...

When making our QSO skip maps one of the issues we encounter is that the lines from our station to the F2 layer don't always start right at the ground. This seems to be an artifact of CZML and the fact that the Earth is not a sphere, but rather an ellipsoid, and even then, there are all those hills and mountains. The initial QSOs can wind mapped as up coming from underground: or, they can wind up starting from above the surface of the Earth In any event, it's been necessary with each map to adjust the elevation height of our station. I've yet to find a parameter to set in a czml that makes the starting point always be on the ground. "clampToGround" works for polylines that are always on the ground, but not polylines whose next point has an altitude greater than zero as the ground station to F2 layer polylines do. I added a feature into the JavaScript mapping application this week that allows me to adjust the height of all of the QSO's starting points at...

 I've read a little bit about 'local data' lately, and I've become fairly excited about the idea. Two of the features of the concept that I like are that your data should be your own, not stuck behind a corporations gated off wall on the internet and that you should have a copy of that data that lives on physical media within arms reach. I won't venture into the second one today except to say that with Google, in particular, somewhat constantly doing away with applications it becomes bored with and Amazon deciding it has and then has not rights to serve movies I 'purchased', having my data in a usable format and in arms reach physically makes more sense than I'd like for it to. Today, I'm going to talk about the first thing, being in control of your own data to use as you see fit. As someone who develops open source apps, there are benefits to everyone beside me holding on to their own data. The biggest one for me being that I don't have to figu...

 What a gorgeous day to hang out in the mountains! I drove a bit outside of Las Cruces, NM over the weekend to play radios! KO6BTY first activated this very spot in the park using TouCans and a vertical antenna in December of last year. I used the same setup this time with one change. Instead of using a tent pole as a mast, I actually remembered to take the carbon fiber fishing pole we usually use off the airplane with me this time. You can see TouCans enjoying the view out over the White Sands Missile Range in the picture to the left.  Propagation wasn't spectacular either afternoon, so no off-the-continent DX, but I did get pretty good coverage of the United States and a few QSOs into Canada! I'll have more updates on the park activation later, but for now, here's the animated QSO map.

 Soldersmoke opens another rabbit hole! This time, it's car portable satellite morse code (CW) QSOs. The video Bill referenced pointed me at an SDR for the geostationary ham radio satellite where I was treated to satellite Morse code pretty quickly courtesy of DJ4FF. And! It turns out he operates satellite through the sunroof of his car ! Videos

 Remember saving software on audio tapes? No, of course I don't either. I mean really, who's that old? OK, it's me. I am.  What brings all this up? a post from soldersmoke about tapesponding . One of the many amazing things the video mentioned there reveals is that pirate radio stations used to broadcast software... You know... The kind you saved to audio tapes! Back in the '80s, I pestered my parents for an entire year for a Timex/Sinclair 1000. Of course I saved programs on audio tapes! The reference to pirate radio broadcasts of software was something I'd never thought of, and it's sheer genius in my opinion. How cool! As a kid in the early '80s, I used to tape record conversations and broadcasts using my dad's shortwave receiver, an EAC R-390 A/URR. I wish I'd held on to the tapes! The kids here who are 14, 12, and 10 are still audio tape afficianados thanks to our '95 Isuzu Trooper complete with tape deck.  Perhaps we'll have to try ...

 Gaaackkkkk the AM broadcast interference!!!! Gaaasssspppppppp! Still though, the POTA went really, really well and camping with the gang, (aged 14, 12, and 10), was a blast. We haven't camped in forever! The Park Angel Island State Park, US-1123, no surprise perhaps, is an island. It's just off the coast of San Francisco, Oakland, and Tiburon. It served a similar purpose to Ellis Island once upon a time. Getting There No surprise to anyone that regularly reads the blog, we, of course, took public transit to the island. The gang were carrying most of our camping gear. We took BART downtown, had lunch at the Irish Bank, the Irish pub the gang grew up around over the last decade or so, and then hopped the ferry to Agnel Island. I stopped by The Palace on Montgomery and Market before meeting the gang on the way to the ferry terminal. If you think you've seen that ceiling before in a certain movie with Michael Douglass, it's because you have. If you'd like to know what ...

 TouCans is back up and running! The battery noise is also just gone! One issue caused both the noise and the key stoppage. The ground wire connection from the keyer relay was in the process of breaking away during the fixes last week. This led to the noise I heard in the rig. It also led to the wire, of course, actually detaching which kept the keyer from working. KO6BTY soldered the ground connection back this morning, and TouCans is back up and running well! Here's what the noise before the fix. This is what a wire breaking in TouCans does. The new battery is doing a good job. Here's how the RBN saw TouCans right after the fix.