[time-nuts] nubie querie

[Bob Camp]

Hi

So can you / do you actually *see* the last grain in the hourglass in question? If we are looking at something that is not observed in "normal operation" we have re-defined the function of the device.

Bob


On Mar 5, 2010, at 10:50 AM, Raj wrote:

> The variability will depend on friction between particles and the last particle's physical slide down the glass!
> 
> At 05-03-10, you wrote:
>> Hi
>> 
>> Even defining when the sand timer is "done" is not a real simple thing. Waiting for that very last particle to drop may not be the best approach. 
>> 
>> Bob
>> 
>> 
>> On Mar 5, 2010, at 9:20 AM, Tom Holmes, N8ZM wrote:
>> 
>>> tvb...
>>> 
>>> Not to kick sand in your face, but it seems that in order for your automated
>>> turn-over device to work, as well as to accurately measure the time
>>> intervals, you would need a means to determine when the sand quits flowing.
>>> Possibly an accelerometer or microphone, with the added benefit of being
>>> able to hear the close-in phase noise.
>>> 
>>> I admire your dedication to monitoring the hour long periods of the sand
>>> timer so diligently. Truly a time-nut!
>>> 
>>> Regards,
>>> 
>>> Tom Holmes, N8ZM
>>> Tipp City, OH
>>> EM79xx
>>> 
> 
> 
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