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Comment by almostnormal | Hacker News Reader

Kitchen appliances don't contain real clocks that keep time autonomously, but simply use the frequency of the power grid. So the solution is not to change the time but the frequency.

During some hours of the night increase/decrease the frequency to let the "clocks" run faster/slower, so they gradually adjust for the next day.

That could even be stretched out over multiple days, maybe two weeks, which would it make much easier for humans to adjust, too.

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The frequency of the power grid thing applied to old alarm clocks, but I don't think electronics have generally used this approach for a few decades; RTC's and microprocessors that embed them are cheap.

I think that in my microwave they've even cut costs on that. Both Etna oven and microwave drift a few minutes each month.

I would really appreciate it if my clock actually ticked at one second per second.

In fact, I shouldn't even have to question that.

Wait, what?

There is nothing insane about running the national power grid at 40hz for a week in order to slow the microwave clocks down!

50Hz can be reasonably handled by 'worldwide' power transformers (thanks EU!)

Not by synchrononous electric motors. Like those used in nearly every industrial machine. Those spin slower when grid frequency decreases, which will cause major problems in many cases.

either run those motors for 120% duty cycle, or abolish daylight savings time

both sound equally incredulous for different reasons

TIL. I'm still in shock.

edit: This explains why my oven clock, which I correct frequently, is always WILDLY inaccurate — either too fast or too slow.

In the EU the grid prioritizes frequency over voltage. If production is slightly below load, voltage is decreased, not frequency. If things go really bad and frequency drops, too, they'll fix that by running at a slighly higher frequency later. Clocks that have been fixed in the meantime require to be fixed a second time.

A deviation of 6 minutes was reached and fixed in 2018.

https://arstechnica.com/tech-policy/2018/04/european-grid-di...

I have no idea if that kind of strategy is applied elsewhere in the world.

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