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pps43

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if you know the modulation and the frequency the receiver uses

Number stations on short waves all use AM, so you know the modulation. But you don't need to know it, superhet works the same way with any modulation. You need to know the number station frequency, receiver's intermediate frequency, and guess whether its above or below.

in such a way that there is absolutely no power radiated out of the reception antenna.

I'm not saying there is absolutely no power radiated out of the reception antenna, only that there is not enough power to reliably detect and localize, given the noise and interference from other sources.

If you want absolutely no power radiated out of the reception antenna, you can still do it. Feed some local oscillator frequency, inverted, into the antenna to cancel the remaining leak. But as far as I know, nobody bothers since some leakage is not a problem.

Any kind of magnetic or capacitive coupler is bi-directional.

True, but in many designs there's also at least one transistor stage in the preamp, and that is not bi-di. There is some stray capacitance between collector and base, but not much.

Maybe with today's hardware capabilities it would be possible to pull the whole thing into the digital domain at a very early stage

It is possible, but unnecessary. The last radio I built has quadrature sampling detector with FST3253 and handful of op-amps. Most SDRs also do I/Q sampling with two slow ADCs, much simpler than a single high-speed ADC.

There's a good reason why many laws in math and physics have two or three names. They are oftentimes discovered simultaneously by several people and it's not always possible to tell who was first.

The tests themselves are fine, false positives are due to human error:

"The high specificities (usually 100%) reported in PCR-based tests for SARS-CoV-2 infection do not represent the real-world use of these tests, where contamination and human error produce significant rates of false positives."

New York reports positivity rate below 1% for a while now, so false positive rate cannot be 2.3%.

we were taught about the idea of overpopulation in school

That's a problem with school education. They give the wrong models. Exponential growth is impossible in nature because at some point it runs out of steam and fizzles out. Logistic curve or probit is a much better abstraction.

I beg to differ. One of my most vivid educational experiences is of my teacher calculating approximate square root on the side of the blackboard when he needed it for something completely unrelated. To me it felt like he was riding a unicycle or swallowing a sword.

Seeing that the audience was perplexed, he reluctantly took a five minute detour and explained Newton-Raphson algorithm, at which point the unbelievable circus trick suddenly became trivial.

I have opposite experience. My parents did not help me with homework beyond first or second grade. After that it was my responsibility, like cleaning my room. I was near the top of my class.