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In the 80s my uncle had digital clocks that used an antenna to tune into the atomic clock time signal that (was/is?) broadcast nationwide. I've long wished that
by jaggederest 10mo ago
In the 80s my uncle had digital clocks that used an antenna to tune into the atomic clock time signal that (was/is?) broadcast nationwide. I've long wished that it was incorporated into stoves, microwaves, essentially everything that isn't an internet device (yet... sigh)
Sadly I think the actual antenna and hardware were relatively large since it's a long wave signal, but maybe with SDR it'll all fit on the head of a pin these days.
- jasonwatkinspdx 10mo ago> Sadly I think the actual antenna and hardware were relatively large since it's a long wave signal, but maybe with SDR it'll all fit on the head of a pin these days. Unfortunately there's no real way to cheat physics as far as shrinking a wavelength goes. With RF antennas about the best you can do is a major dimension 1/10th the frequency of interest.
- namibj 10mo agoThere are many DCF77 receivers in Germany that are contained in a square box that's barely large enough for a AA battery; the rest of the square contains the motor/gears and the electronics/receiver (incl. a ferrite loopstick antenna). The wavelength is around 3.8km...
- jasonwatkinspdx 10mo agoYeah, that's because it's receiving an extremely narrowband signal accumulated over a long window so it can suffer the trash efficiency I'm talking about.
- raron 10mo ago> atomic clock time signal that (was/is?) broadcast nationwide Probably DCF77 or WWVB. > I think the actual antenna and hardware were relatively large since it's a long wave signal Casio has some normal sized wristwatches that synchronizes to DCF77, it would definitely fit into a stove, microwave, or basically anything.
- jaggederest 10mo agoI believe it was a longwave broadcast so probably WWVB which would apparently imply a 60mm antenna, but it was a standard old school "GE digital clock radio" form factor so size wasn't at a premium.