Of course there are also the so called "atomic" clocks and wrist watches that use miniature WWVB receivers to lock to the slow 60 kHz carrier AM modulated time code from Boulder CO. I have a bunch of different time sources in my home lab from a WWVB comparator with hoola hoop loop antenna, a rubidium oscillator, a GPS timing receiver, a shortwave receiver tuned to WWV on 10 MHz and my computers that periodically sync to Internet time servers. that said, I no longer wear a wrist watch as my cell phone provides a sufficient time check for my purposes. When it comes time. twice a year to reset those hidden real time clocks that cannot auto correct for daylight savings versus standard time, it becomes an adventure. I now have a list of over 60 devices that require such attention from me!
I've experienced the same thing with my microwave, RonChownyk. When I'm not sure how long to zap something, I'll open the door and check the heat. If it needs more time, it invariably re-starts in the the reverse rotation. That happens consistently.
Not the same company but the page linked below has a similar type clock. It's actually quite funny to see people's reaction when they see it for the first time. You don't even need a novelty clock, just turn any standard wall clock upside down and watch how many people get confused.
I saw the same Bizarro cartoon after I posted about them: the strip reran this one last Sunday. The Mayan calendar carver actually says "I ran out of room after 2012." The other guy says something like "This will really freak someone out some day."
And thanks to fire-iron.biz for the reading instructions. Sounds really confusing in practice. Glad I wasn't one of their guests.
Our microwave oven is no more than a few years old. It has one of those turntables designed to provide uniform heating all the way around whatever is in the oven. One day I noticed that the direction of rotation of the turntable is completely random - some times it turns clockwise, sometimes counter-clockwise.
In regard to AC clocks versus quartz crystal clocks: Last year the Programmable Controller class I teach built a digital clock with an Allen-Bradley SLC-5/04 controller and six very large 7-segment displays - hours, minutes, and seconds. It is using a one second timer for its time base. Except for having no provision to account for Daylight Savings Time, it has been keeping very accurate time since May 2010.
The "1" was in place of "11", "2" in place of "10", ect. The motors were changed to run in reverse so the hands turned CCW to correspond to the CCW number layout. The somewhat confusing part was that the numbers themselves were in reverse as if looking at lettering on a storefront window from inside the store.
...LOL...Bizarro Cartoon...clocks, and calendars... There's a Bizarro cartoon from a couple years ago...Two mayans are standing near this 4 foot diameter stone...calandar...filled completely with symbols...the one guy, with a mallet and chisel in his hands... says to the other..."I ran out of room, this will really freak someone out later.."
This brings back great memories! When I was about 10 years old I started working with my dad, an electrician. One summer we were changing a house service and dad asked if I wanted to go up on the roof and cut off the utility power. I ran up the ladder and cut the wires and yelled down "Okay, its off!" He yelled back "So why are the light still on?" It was a city row home, and I had cut the neighbors power! We reconnected it and left the home owner a note. The next day the lady called and said everything seemed to be okay, but her kitchen closk was running backwards. Dad told her to unplug it and push the hands forward slightly, then plug it back in. It did restart in the right direction this time.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.