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A comment on Simple streetlight hack could protect astronomy from urban light pollution. Parent comment

Re:Simple streetlight hack could protect astronomy from urba... by Evidlo on Saturday November 18, 2023 @01:26PM (#38322709)
Wavelength of FM radio is about 3m, so you only have to be a few centimeters shifted to be seeing an entirely different phase and be out of sync.
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Re:Simple streetlight hack could protect astronomy from urba... by p1mrx on Saturday November 18, 2023 @07:51PM (#38326980)
If the LEDs blink at 150 Hz, then a single on-off cycle has a "wavelength" of 2000 km.

The wavelength of the control signal doesn't seem relevant.

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Re:Simple streetlight hack could protect astronomy from urba... by quickthrower2 on Saturday November 18, 2023 @08:08PM (#38327133)
Plus you just add a position based delay. This is quite the bikeshed!
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Re:Simple streetlight hack could protect astronomy from urba... by p1mrx on Saturday November 18, 2023 @08:17PM (#38327207)
How does the LED know its own position? At that point you might as well abandon FM and use GPS.
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Re:Simple streetlight hack could protect astronomy from urba... by quickthrower2 on Saturday November 18, 2023 @08:40PM (#38327377)
Send a few bytes of data onto the SD card on lamp installation. If GPS can do it all in one then that is probably better given how cheap the units are these day.
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