I recently started switching off at the wall appliances which, in the past, I used to leave on standby overnight, (a DVD player, for example).

Some of these appliances have non-battery-backed clocks.

I'd like to be able to say to each of them, 'Good morning, microwave oven, good morning DVD player, it's now 8:00 am, I trust you slept well'.

Well, I can do that already, but what I'd also like to do is poke a standard bit of hardware into a standard socket on each appliance in turn, so that it is immediately reminded of the time, without my having to navigate any kind of menu system or dig out the manuals.

This 'standard bit of hardware' could either be a small digital clock/watch with a prong on it, or a double-ended bit of cable, whose other end might fit into a socket in some other device whose clock *is* battery-backed (a watch, a mobile phone, a laptop, etc.)

A standard hardware interface of this kind would also come in handy when the clocks go back or forward for daylight-saving purposes; just set one clock by hand, and then give all the others a quick poke.
-- pertinax, Oct 27 2007

The power company could distribute a clock signal over the mains
-- BunsenHoneydew, Oct 27 2007


If you're going to install this "standard interface" on all new appliances, wouldn't it be simpler just to have them battery- backed anyway? (I suspect that most new appliances are battery-backed anyway). This is a bit like calling for all new cars to have a standardized socket for the starting handle, shirley?
-- MaxwellBuchanan, Oct 28 2007


We could have them listen to the BBC (Domestic/World service: Delete as applicable) and register the time pips. 'pip pip pip pip pip, This is London, The time now is 6:00 am GMT' -> Voice recognition -> time setting.
-- vincevincevince, Oct 29 2007


Well there are quite a few ways to do this already actually. But almost nothing uses them.

Network Time Protocol is used to synchronize computer clocks across networks of all sizes.

Also, there are low frequency (long range) radio stations that broadcast the time and their signature in a standard, machine-readable format.

Some local stations (such as NPR in the US) mirror this signal (in radio terminology, this is known as a "translator").

There are a few digital clocks (typically in the $50 and up range) that synchronize themselves automatically to this signal. Usually the term "atomic clock" is found on the box (although, technically the clock itself is not atomic, it just relies on a remote atomic clock).

Cable and satellite set-top boxes and cell phones also synchronize themselves with their own signals.

I hereby bun this idea, since I know of no microwave ovens, DVD players, stoves, and other such devices that incorporate this feature.

Also hardly any appliances use time as a power saving feature.
-- Spacecoyote, Oct 29 2007


//If you're going to install this "standard interface" on all new appliances, wouldn't it be simpler just to have them battery- backed anyway?//

Being battery backed - or synching to another untrustworthy device - is a waste of time as all you'll do is propogate a bad time stamp.

The suggestion of using the Navy (or Greenwich) wireless clocks is a good one; along that lines may I suggest another mechanism: use a GPS chip, which are so cheap nowadays they can even be embedded in every telephone :-/ GPS gets an accurate time signal as well as knowing its location, and they seem to work fairly well indoors nowadays. (Which can't be said for my self-setting 'atomic clock' which has to sit by the window :-( )
-- gtoal, Oct 29 2007


//The power company could distribute a clock signal over the mains//

I suggested this idea years ago, but it got fishboned so badly, I deleted it.
-- harebrained, Oct 30 2007


//radio stations that broadcast the time / clocks / that synchronize themselves automatically to this signal.//

And an evil practical joke is to alter the hands/circuitry of such a clock so that it always shows a few minutes fast/slow. If the owner attempts to set it by hand, it always auto-synchs itself to the "wrong" time.
-- BunsenHoneydew, Oct 30 2007


Or; considering a microwave is for cooking food and a DVD player is for playing DVDs... remove clocks from them all.
-- vincevincevince, Oct 31 2007


//Or; considering a microwave is for cooking food and a DVD player is for playing DVDs... remove clocks from them all//

And save electricity at the same time. Think of all the devices we have with unnecessary clocks on them, running 24 hours a day, slowly trickling the juice. Each device itself isn't much, but altogether? Wow.
-- Noexit, Oct 31 2007


//running 24 hours a day, slowly trickling the juice//
But some only go up to 12 hours, with a nifty 50% power saving.
And the one on my oven flashes after every power cut, so it doesn't use power for half of the time.
-- Ling, Oct 31 2007


Could you just have a clock with an adjustable "start time hour off-set" so when the power goes on the clock reads 08:00 instead of 00:00
-- Iridium7, Nov 02 2007


Clearly what is needed here is a small robot with pokers that can be taught to adjust the time in all appliances. You go round once resetting all the clocks *with* the robot, it remembers the sequence, and then everytime you tell it to, it makes sure that all clocks are synced with it's own radio controlled clock. Just don't move the appliances without telling your robot first.

Although, it may be cheaper to replace all your non-battery-backed appliances.
-- TheLightsAreOnBut, Nov 02 2007


Maybe you could use Wi Fi to access an NTP server?
-- kevinthenerd, Jan 12 2009


I kind of said that already.

There is a variant of NTP called SNTP which is designed for embedded systems. In my opinion, a SNTP signal distributed over the power line similarly to what [BunsenHoneydew]/[harebrained] suggested, would be the way to go. A small device plugged into the outlet could provide the signal, rather than the power company.

Then again, I'd rather clocks were clocks and microwaves were microwaves.
-- Spacecoyote, Jan 13 2009


//I'd rather clocks were clocks and microwaves were microwaves//
But then how would we get our MASER-based atomic clocks?
-- coprocephalous, Jan 13 2009



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