Hello all first time poster,
recently i moved to the USA from Ireland for college, i brought with me
my alarm clock which had served me well back home.
However whenever i plug the clock in and set the time and alarm,
i awake next morning to find the alarm didn’t go off and the time is running fast by a couple of hours.
Recently i charged my phone, and somehow the date went forward a day!
For both the alarm and phone i used the same adapter.
So my question is my adapter broke? Or rather more worrying is my roommate trying to mess with my head (unlikely but we can’t rule this out)
I think that this is because the time on an electric clock is based on the frequency of the power, and we use a different power rate here in the states. So, without a transformer, your clock won’t keep proper time. That’s a guess, IANAElectrician.
Even with a transformer, the mains frequency in the US will still be 60Hz while Europe uses 50 Hz.
Not much you can do about it, cheaper to replace it with an American one.
Most digtal clock modules have a pin to select the power frequency. It simply sets the divide ratio used to get the seconds. However they are so cheap that it is hardly worth bothering messing about unless you enjoy the challenge. (Me, I would be inside the clock with a soldering iron in seconds.)
Many (but not all) mobile phone carriers provide time updates. This can be both useful and annoying. So the time on your phone can be set from the cell. It may be simply that someone got the day wrong when updating something. Phone cells have a very very good idea of the time (either using atomic clocks or a dedicated GPS based time receiver.) But since most technical systems use UTC for internal time, they probably keep a local time offset, and maybe some simply got it wrong.
The standard voltage in Ireland (according to google) is 220 volts at 50 Hz. So not only is the frequency off, but the voltage is quite a bit off as well. You are lucky that the clock works at all.
Some alarm clocks use an internal crystal to generate their time base. Others use the main voltage frequency. Yours is obviously the second type because it is counting time wrong.
Unless the clock is specifically designed to work over a wide range of voltages (which most aren’t), your ringer circuit was likely running at half the voltage, which would have produced half of the current for the ringer, for a grand total of one fourth the power. That could easily explain why you didn’t hear the ringer. It rang at the wrong time and was likely very quiet, if it worked at all.
If you are going to go to extremes like Francis Vaughan and break out the soldering iron, you’ll likely need to do a transformer swap as well as rewiring the frequency select pin on the timer chip. For everyone else, just buy a new alarm clock. It’s not worth the effort.
I know that when they changed the dates for DST a few years ago, they didn’t change the towers. My phone was wrong for about a week, and couldn’t be set to the right time.
Just get a battery powered alarm clock. Mine has the time automatically set by WWVB and automatically adjusts for DST. I only have to replace the battery every couple of years and I don’t need another power cord to my bed side table and I don’t have to worry about power outages.
I solved that problem by turning off the feature that automatically set the time. Now I have to manually set it on the time-change dates, but that’s better than having it be wrong.