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fr0sty

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+1 to the above.

Implementing a mental dit/dah decoder + lookup table is the shortest path to being able to decode written CW ` _ . ___ _ ` but it will cause you problems trying to receive faster CW since you can't count, assemble, lookup fast enough to receive at more than 5-8WPM. And even then you are generally doing "keyboard copy" where you write down the letters as you hear them and then go back to actually read the message you received later.

I'll put in a vote for: https://lcwo.net/ (Learn CW Online)

If your goal is to be "conversational" in CW I suggest you crank up the character speed until you are not able to count individual dits/dahs anymore. This will probably be somewhere in the 25-35WPM range. The goal is "instant character recognition" where you hear the sound/shape of the entire character rather than counting elements, assembling them in your head, and doing a mental hash lookup on the result.

If you have trouble receiving or copying down the 5letter groups at this speed resist the temptation to add "farnsworth" spacing (extra gaps between letters). Instead increase the word spacing until you have enough down time in between to get everything copied.

On the subject of the Derby, this was originally published as "The Kentucky Derby: An Oral History": https://www.newyorker.com/magazine/2019/05/20/the-kentucky-d...

Such "Oral History" articles were quite popular for a time* and the fist time I encountered this article it still had its original title. I'm sad that it was not retained since the url now gives away the punchline.

* https://www.vulture.com/article/an-oral-history-of-disney-th...

I'd love to find a good number on the daily mileage of the median passenger car in the US. The average looks to be around 30-35mi/day but the median is probably a small fraction of that. Why would you want your battery pack to be 10x oversized for your typical day?

I think a more efficient solution would be series-hybrids with small onboard generators for range extension. Minimize weight/cost of the battery pack while maintaining the ability to drive cross-country without frequent charging stops.

Some light googling gives me 390B kilometer-tonnes[1] in Europe and 1.6T ton-miles[2] in the US for 2019. So that is 6x the freight movement.

The US rail network also >2x longer than Europe[3] (360,000km vs 151,000km).

[1] https://ec.europa.eu/eurostat/statistics-explained/index.php...

[2] https://www.statista.com/statistics/198443/us-class-i-freigh...

[3] https://www.floridarail.com/news/6-key-differences-between-a...

https://www.poynter.org/fact-checking/2023/why-train-derailm...

Most derailments are in train yards. Few cause injuries, fewer cause deaths, and only a handful involve hazardous substances. I don't say that to downplay the mess in OH/PA, but just to make sure the base-rate is understood.

And if you want to compare to europe it looks like US freight rail volume is at least 6x as large. Also no idea if/how they count "fender bender" derailments in switching yards. US standard is >$12k in damage according to TFA.

Is AM radio dead? 3 years ago

Amateur radio is for 2-way communication only. No "broadcasts" allowed (with some _very narrow_ exceptions).

It isn't really clear in the video, but that is a 4 layer board and there is another ground plane layer elsewhere. The heater loop doesn't connect to any components.

This accident? https://en.wikipedia.org/wiki/SL-1

"Stationary Low-Power Reactor Number One, also known as SL-1 or the Argonne Low Power Reactor (ALPR), was a United States Army experimental nuclear reactor in the western United States at the National Reactor Testing Station (NRTS), later the Idaho National Laboratory, west of Idaho Falls, Idaho. It experienced a steam explosion on the night of January 3, 1961, killing all three of its young military operators, and pinning one of them to the ceiling of the facility with a reactor vessel plug. The event is the only reactor accident in U.S. history that resulted in immediate fatalities.

+1 for HamStudy.org which is an excellent resource. They include "explainer" cards for each question which often contain links to other material which are a great jumping off point for going as deep as you care to go on any individual topic.

I used the hamstudy website almost exclusively for getting my license and was able to pass all three tests (General, Tech, Amateur Extra) in one sitting. I had to set for a physical test at a local club's monthly meeting, but now organizations like GLAARG are proctoring remote tests via zoomso you can gest more or less 'on demand' from home.

[follow] a convention of including unit names in identifier names.

appending units to identifiers helps, but it relies on a developer's eyeballs to spot any errors. It would be infinitely preferable if the type system would simply enforce this for you and developers not have to expend cycles reasoning about this stuff themselves.

My apologies. It appears Morse Expert is Android only, sorry. I tried to do a quick search on my way out the door earlier and was mistaken.

What were you expecting to find?

$1068 at 85% efficiency is $907 "effective" heating dollars. $971 at 94% efficiency is $912 so that passes a basic sanity check.

The major improvement is efficiency c es from runnimg higher volume at lower temperature differentials. This allows the "cold" side of the furnace/boiler to condense the water vapor in the combustion gasses and capture its latent heat.

little plastic bags are a bit too flimsy and difficult to handle/organize for my taste.

I settled for small "coin envelopes" labelled with pen and placed on end in a deep shelf bin.

For patients with chronic conditions if the doctor determines the patient should be seen to evaluate their condition in 30 days before a new script is written

I'm reasonably cynical about lots of things, but I would be absolutely shocked if a pharmacist can give you 90days of pills when handed a 30day (no refills) prescription.