Comment by joecool1029
9 hours ago
> A friend told me once that his mouse stops working when someone is using the microwave. His room was on the backside of the kitchen.
I had to disable a 2.4ghz access point a couple years ago because a bathroom had a passive IR detector for the light switch that would never let the light shutoff. Because detecting IR is a pretty weak signal, I guess these switches amplify it. The issue is the circuit also acts as a weak antenna for 2.4ghz and thinks its seeing IR when it's actually just amplifying and seeing the 2.4ghz beacon signal.
RF gets weird. Something I've thought about over the years is how my FM radios at my old house would sometimes pick up aviation radio which should be AM well above a tuned FM frequency. Apparently this is due to the common design being a superheterodyne receiver which comes with a few quirks (such as causing some small interference itself when it's receiving).
If you strum an electric guitar and let the hertz of the string fall through the range of AM radio the amp will briefly pickup AM radio stations. Not that you can decipher anything but you recognize voices as it travels past the station.
That's not because of the frequency of the guitar but because the guitar functions as a very nice antenna (long piece of metal (the strong) + a coil forming a tuned circuit), what happens is that your hands create a very temporary partial diode where you touch the strings!
Such naturally occurring diodes are an interesting phenomenon (in this case: the salt in your sweat interacting with the steel of the strings) and were the basis of the very first radio receivers after the 'Coherer' (which is a word that has fallen out of use so far that it registers as a spelling error on my browser!).
That may be one explanation, but more broadly with analog audio it is actually quite difficult NOT to end up with an AM receiver.
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Too late to edit: strong => strings. sorry!