The turntable of my GE microwave oven makes one revolution every ten seconds. For reasons I can only attribute to the designer's whim, the turntable reverses direction with every new start and continues to turn for some fixed time after the cycle times out. A heating duration of an integer number of seconds times tens carries my coffee somewhere toward the back. Without knowing how long the "afterglow" period lasts, how can I heat my coffee to that the cup will be at the front when the heating finishes? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Off-topic teaser
Started by ●April 16, 2005
Reply by ●April 16, 20052005-04-16
Stop and start it half way through. "Jerry Avins" <jya@ieee.org> wrote in message news:nK6dnWvg5Iyk0vzfRVn-jA@rcn.net...> The turntable of my GE microwave oven makes one revolution every ten > seconds. For reasons I can only attribute to the designer's whim, the > turntable reverses direction with every new start and continues to turn > for some fixed time after the cycle times out. A heating duration of an > integer number of seconds times tens carries my coffee somewhere toward > the back. > > Without knowing how long the "afterglow" period lasts, how can I heat my > coffee to that the cup will be at the front when the heating finishes? > > Jerry > -- > Engineering is the art of making what you want from things you can get. > �����������������������������������������������������������������������
Reply by ●April 16, 20052005-04-16
Jerry Avins wrote:> Without knowing how long the "afterglow" period lasts, how can I heat my > coffee to that the cup will be at the front when the heating finishes?Get a different oven? ;-) My first microwave didn't have a turntable; it used a stirrer in the microwave path instead. Why have manufacturers decided that turntables are better? They sure waste a lot of space! Anyway, my current microwave turntable seems to make exactly one revolution every ten seconds -- it always presents the handle of my mug to me! And it does reverse direction on each activation as well. (Which is the real answer to your question.) -- Dave Tweed
Reply by ●April 16, 20052005-04-16
"Jerry Avins" <jya@ieee.org> wrote in message news:nK6dnWvg5Iyk0vzfRVn-jA@rcn.net...> The turntable of my GE microwave oven makes one revolution every ten > seconds. For reasons I can only attribute to the designer's whim, the > turntable reverses direction with every new start and continues to turn > for some fixed time after the cycle times out. A heating duration of an > integer number of seconds times tens carries my coffee somewhere toward > the back. > > Without knowing how long the "afterglow" period lasts, how can I heat my > coffee to that the cup will be at the front when the heating finishes? > > JerryA very practical problem indeed! Add or subtract 5 seconds from the set time?
Reply by ●April 16, 20052005-04-16
Symon wrote:> Stop and start it half way through. > "Jerry Avins" <jya@ieee.org> wrote in message > news:nK6dnWvg5Iyk0vzfRVn-jA@rcn.net... > >>The turntable of my GE microwave oven makes one revolution every ten >>seconds. For reasons I can only attribute to the designer's whim, the >>turntable reverses direction with every new start and continues to turn >>for some fixed time after the cycle times out. A heating duration of an >>integer number of seconds times tens carries my coffee somewhere toward >>the back. >> >>Without knowing how long the "afterglow" period lasts, how can I heat my >>coffee to that the cup will be at the front when the heating finishes? >> >>Jerry >>-- >>Engineering is the art of making what you want from things you can get. >>�����������������������������������������������������������������������That almost does it, but not quite. When it's manually stopped, by opening the door, by pulling the plug, or with the reset button, it stops immediately. One way would be to stop it as soon as it's finished, but what I had in mind was choosing to intervals whose sum is the desired time and using them in succession. Since the second overshoot -- hereinbefore called the afterglow -- is the same angle as the first but in the opposite direction, it cancels the first. (In practice, I set the cup at the edge of the turntable with its handle pointing toward the center. Removing the cup is then easy no matter where it stops. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●April 16, 20052005-04-16
Fred Marshall wrote:> "Jerry Avins" <jya@ieee.org> wrote in message > news:nK6dnWvg5Iyk0vzfRVn-jA@rcn.net... > >>The turntable of my GE microwave oven makes one revolution every ten >>seconds. For reasons I can only attribute to the designer's whim, the >>turntable reverses direction with every new start and continues to turn >>for some fixed time after the cycle times out. A heating duration of an >>integer number of seconds times tens carries my coffee somewhere toward >>the back. >> >>Without knowing how long the "afterglow" period lasts, how can I heat my >>coffee to that the cup will be at the front when the heating finishes? >> >>Jerry > > > A very practical problem indeed! > > Add or subtract 5 seconds from the set time?7 is about right. But that's a priori knowledge. -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●April 16, 20052005-04-16
David Tweed wrote:> Jerry Avins wrote: > >>Without knowing how long the "afterglow" period lasts, how can I heat my >>coffee to that the cup will be at the front when the heating finishes? > > > Get a different oven? ;-) > > My first microwave didn't have a turntable; it used a stirrer in the > microwave path instead. Why have manufacturers decided that turntables > are better? They sure waste a lot of space!My first microwave oven didn't have a turntable either. The stirrer was turned by the magnetron's cooling air and eventually stopped responding (although it turned freely enough). I increased the airflow by augmenting the shroud that channeled the air. Maybe there's a long-term reliability issue.> Anyway, my current microwave turntable seems to make exactly one > revolution every ten seconds -- it always presents the handle of > my mug to me!It must stop immediately then, or continue for exactly ten seconds.> And it does reverse direction on each activation as > well. (Which is the real answer to your question.)Why reverse? A reversible motor costs more, and the switch to select direction isn't free.> -- Dave TweedJerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by ●April 16, 20052005-04-16
Jerry Avins wrote:> > Without knowing how long the "afterglow" period lasts, how can I heat my > coffee to that the cup will be at the front when the heating finishes?1) Put the cup first in the back, so you'll get in the front. 2) Put the cup in the middle, so there is no problem. ;-) bye, -- piergiorgio
Reply by ●April 16, 20052005-04-16
"Jerry Avins" <jya@ieee.org> wrote in message news:9YadnR6Ov5Q_9fzfRVn-rg@rcn.net...> Fred Marshall wrote: >> "Jerry Avins" <jya@ieee.org> wrote in message >> news:nK6dnWvg5Iyk0vzfRVn-jA@rcn.net... >> >>>The turntable of my GE microwave oven makes one revolution every ten >>>seconds. For reasons I can only attribute to the designer's whim, the >>>turntable reverses direction with every new start and continues to turn >>>for some fixed time after the cycle times out. A heating duration of an >>>integer number of seconds times tens carries my coffee somewhere toward >>>the back. >>> >>>Without knowing how long the "afterglow" period lasts, how can I heat my >>>coffee to that the cup will be at the front when the heating finishes? >>> >>>Jerry >> >> >> A very practical problem indeed! >> >> Add or subtract 5 seconds from the set time? > > 7 is about right. But that's a priori knowledge. >Well, I was going to be more mathematical initially. So there are a lot of assumptions. Now one of the assumptions has to be that the "data" was bad in the beginning. Here's what I got from your "statement": 1 revolution in 10 seconds and I assumed for all modes. You program it for N*10 seconds where N is an integer. It stops in the back - at 0.5 revolutions. 0.5 revolutions is 5 seconds at 0.1rps. If it stops in the back at 0.1rps then the total run is R+0.5 revolutions where R is an integer So, the overrun must be K+0.5 revolutions where K is an integer and R = K + N So, there must be a flaw in the data or the assumptions...... :-) I like putting it in the middle!
Reply by ●April 16, 20052005-04-16
Piergiorgio Sartor wrote:> Jerry Avins wrote: > >> >> Without knowing how long the "afterglow" period lasts, how can I heat >> my coffee to that the cup will be at the front when the heating finishes? > > > 1) Put the cup first in the back, so you'll get in the front. > 2) Put the cup in the middle, so there is no problem. > > ;-) > > bye,You seem to assume a time of extra movement. On what do you base that assumption? I wrote only that it is always the same. Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
