Copasetic Flow

 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...

 I just saw a heartening post with respect to the gang's and my quest to see if Agent Sonya could have built her own radio rig. Pete, one of the presenters on Soldersmoke even mentions W1REX in the post in conjunctions with this transmitter schematic : Rex is better known in these parts as the ham that produces RockMite and Tuna Topper kits that populate the innards of Project TouCans. Getting back to Agent Sonya , and also to safety, I was heartened to see Pete mention a supply that had occurred to me for plate voltage and current: nine-volt transistor batteries. Gone forever, apparently, are the B cells of yore, but we can definitely string together 9 volt cells. I wandered if there were issues with this type of supply I'd missed. There aren't! The post and the circuit above also answered a question I'd often wondered about with respect to keying tube circuites. That MPSA92 looks pretty hefty what with its 300 volt rating. It is and it isn't. the maximum curren...

 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...

 Sometimes you need a 3-D visualization of data, and sometimes you don't. I just posted a page  with foF2, hmF2, and MUFD(3000km) map images. All the maps are updated to the latest available data when you open or refresh the page. Map values are available—via tooltips—by hovering your map over the portion of the map your interested in. These maps contain the same data displayed in the 3-D Cesium Ion map . Please let me know what you think. All constructive feedback is welcome!

 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...