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You get the same problem with geostationary satellites, e.g. for satellite TV.

There's period of about 10 days every spring and fall where, for up to 30 minutes every day, the sun transits 'behind' a satellite within the beamwidth of the dish and totally overwhelms the signal at the LNB.



Once upon a time I had a problem with remote control. It woukd stop working from different positions, but from time to time, not always. It took a while for me to realize there’s a heating radiator behind my back in that directions. And it went hotter or colder depending on thermostate. I guess at one point its IR output would overwhelm IR output from remote control.


When I first read this comment I was picturing a hot water radiator behind you, so it sounded unlikely based on the blackbody radiation curve for ~320 K.

But now I realize you're probably talking about an electric heater. Given that their heating elements get so hot that they're putting out visible red/orange light, it seems very plausible that an electric heater could produce enough ~940 nm IR to drown out the signal from the remote.

Thanks for sharing! I will try to keep this in mind when I'm troubleshooting IR remotes in the future.


As I try to recall, it was not typicall remote, the problem was between Nokia 6310i and IrDA transmiter, since that's how you connected phone to the PC back then. Looking at wikipedia, that IrDA was small range, probably low powered, so maybe even very low IR source in the background could create problems? IIRC problem was with the water radiator, which surprised me a lot back then. But we did use electric heaters as well at the time and my memory could be wrong.

Btw. that Nokia 6310i from 2002/3 is still used today by mother-in-law, and original battery still holds for 4-5 days!


I experienced this when I was working on a cable company but sometimes they give out notices when it's going to happen. Random stuff still happens because of the sun. The sun is a very scary thing if you are studying it everyday but most people don't know it.


So an eclipse…of sorts


In this case, transit is the right jargon.

A transit is when the foreground object doesn’t completely hide the background object.

An occultation is when the foreground object hides the background object.

These two situations are collectively called occlusions.

An occlusion is an eclipse if the the observer falls in a shadow.

https://en.wikipedia.org/wiki/Occultation




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