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Ham Radio Extra Class Practice Test | FCC Element 4 Question Pool 2024–2028

Extra Class Practice Exam (Stacked Bars with Toggle Groups) Extra Class Practice Exam Get ready for the FCC Extra Class license exam with this free online ham radio practice test. Our interactive exam tool uses the official FCC Element 4 Question Pool (valid July 2024–2028) and automatically tracks your performance. See your score history, review stacked bar charts of correct vs wrong answers by subelement, and drill down into specific group stats with a single click. This is the first practice run of the free online ham radio practice exams. I fully expect it to be a bit buggy. Please leave any suggestions or bug descriptions in the comments. Exam scores and statistics will be stored in the URL when you click 'New exam/Save Scores' after you complete an exam. To get back to your scores, you should be able to use the histsory feature in your browser, or if you'd rather, copy the link somewhere to put into a browser later. Important Note: To save your s...
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F2 Dev Notes and US-4571 at City College San Francisco a Week Apart

 This week I spent some time tightening up the workflow for comparing F2 ionospheric data across different POTA outings. It turns out documentation really does matter. By writing things down, I’ve not only made the manual process clearer but also pushed the automated flow forward. With GPT-5’s help on documenting proton and electron flux plots, and my own notes on numeric F2 graphs along QSO paths, the project is steadily becoming easier to repeat and share. I put in a little bit of time working on being able to easily compare F2 data for different POTA outings this morning. It turns out documentation really does matter, so I've been focusing a bit more on it. I have a number of tools that allowed me to pull in F2 data quickly. This week I've been trying to spend time pulling them into an automated flow. As I've implemented this flow, I've discovered that I haven't taken the time to document the tools I've already built.  I asked GPT5 to document the solar prot...

KO6BTY’s Late-Night Find: New GOES Proton & Electron Data Meets GPT-5 Charts

Getting back to that Argentina call. One thing KO6BTY pointed out was that the FoF2 numbers didn't look normal. She was correct to an extent. They definitely didn't look like they did a few  months ago. Early morning UTC time, the critical frequency numbers looked like this Critical Frequency at time of QSO to LW2DO in Argentina A few months ago, in February though, they looked like this at roughly the same time of day. Critical Frequency map in February of 2025 a few hours earlier in the day Patterns in the F2 Layer If you're curious how she spotted the difference quickly, we've identified features that are usually on the map, the 'goose', and the 'face.' The Goose The Goose is characterized in profile with it's beak usually outlined in blue. It's circled by the green line above. The Face The Face is perhaps a bit more obvious. Again, it's circled in green. The two low critical frquency zones, (black regions), form the eyes. The black spot ...

Exploring NOAA’s Hidden Gems: New to Me Ionosphere & Aurora Forecast Tools for Ham Radio

  While analyzing the skip path of a a 5-watt QSO I made last week from the San Francisco to Argentina with Project TouCans, I stumbled across a set of NOAA resources that completely changed how I look at ionospheric conditions. From real-time aurora dashboards to animated MUF forecasts and electron flux data, these tools offer hams powerful insights into propagation—and some surprises along the way. I made a grey line QSO from the campus of City College San Francisco to Argentina with our 5-watt Project TouCans rig last week. Last night, KO6BTY and I found ourselves deep in the rabbit hole of ionospheric conditions. What started as curiosity about the Kp index and whether aurora activity might have influenced the QSO's skip path, led us to discover some powerful NOAA resources. From aurora dashboards and global ionosphere forecasts to animated MUF predictions and GOES electron flux data, these tools give ham radio operators new ways to understand HF propagation, F2 layer behavior...

Presidio POTA (US-7889) inside Golden Gate NRA (US-0647) — QRP CW, transit, and a surprise eyeball QSO

  Live portable ham radio from San Francisco’s Presidio with a clean take-off toward the Pacific. Route via PresidiGo, light wire vertical, and a crystal-locked 14.0574 MHz start. I keep local times in the story; the QSO map is in UTC. I arrived downtown at Embarcadero Station at 15:20 PST yesterday with Project Toucans , a portable ham radio. There was a newly married couple, still in their dress and tux, waiting to ride the cable car up towards California and Powell. I was waiting for the PresidiGo bus out to the Presidio. It's a free bus out to the park that passes through downtown several times a day. I hopped on the bus at 4 PM downtown. After a few stops at 4:07 PM PST, the bus was completely full. Interestingly, when we arrived at the first Presidio stop at 4:15, almost everyone got off and exited the Presidio back towards town. I don't know why. The bus winded through the rest of the Presidio towards the transit center. The center is right in front of the new park, cal...

GPT5 Reads Schematics,Does Simple RF Analysis!

 GPT5 helped me understand how the Tuna Topper ][ amplifier in Project TouCans operates yesterday. It started from just this clip of the schematic! While debugging the power supply relay of Project TouCans a few days ago, I noticed an interesting thing. With the Pico-W rig controller plugged into the supply brick TouCans itself was only being doled out twelve volts by the phone charging brick in its base, not the fifteen volts its USB-C adapter was asking for. That mattered the most to the Tuna Topper II  amplifier that drives the five watts to the antenna. I changed the rig so that, for now,  the Pico-W runs on three AA batteries. That upped the supplly to the rig back to its intended fifteen volts. I wanted to understand in broad terms what that meant for the power output of the rig. I tooled around for a bit on paper and spreadsheets before it occurred to me to ask GPT5. I didn't expect to get an answer at all. I definitely didn't expect it to be able to read the sc...

OpenAI ChatGPT Frequently (Always?) Opening in 4o

 Early Sunday morning, the code generated by ChatGPT became noticeably clunky. Why!? I figured it out when this message arrived Ah yes! The LLM that berates me a bit for the code it wrote :) At some point after the release of GPT5, OpenAI started defaulting my chats back to 4o. For me GPT5 is better. I switched back over 5 and a bit later, the code coming out of the LLM was just working, and when it didn't, I got messages like this By the way, at that point GPT5 was fixing code created by 4o when I had specifically asked for: " Also save the vh and vw settings of the subpanel in subpanelsize and resize it to its original extent if the subpanelsize arg is present in a url  " Anyway! GPT5 rocks for me. If you're using the browser UI instead of the API, check to see what model you're using before you go too far down the wrong path.