Harry's watch

[Fred Waldrop <fredwaldrop@yahoo.com>]

No: HPFGUIDX 52681

--- In HPforGrownups at yahoogroups.com, "morgan_d_yyh 
<morgan_d_yyh at y...>" <morgan_d_yyh at y...> 

Morgan Wrote:

This is not my area of expertise, but as far as I know quartz watches 
do require electricity to work. That's why most of them need 
batteries. Battery-less quartz watches were developed recently, if 
I'm not mistaken; they are powered by the movement of the wearer's 
arm. That movement causes a weight to move back and forth, which sets 
a micro-generator spinning which produces electrical energy. The 
electricity is stored in a capacitor (analogous to a battery in a 
battery-powered watch). The electricity then is transmitted to an 
integrated circuit, which keeps the quartz crystal oscillating 
steadily.  
So it would still be something included in the list of instruments 
that can't operate in Hogwarts.


Morgan D.

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Hello all, Fred Waldrop here;
 
Well, I don't know how old anyone is in here, but it really wasn't 
that long ago that no watch used batteries. You just wound them up 
(they were spring loaded, not a generator, and as the 
spring  "unwound", it would make the hands go round and round) and 
they worked. No battery, no generator, no sun panel (they came out 
with those in the late 70's, the sunlight would charge up a battery 
pack, and it would work off that).
You can still buy the "wind up" type watch, mainly in a pocket watch, 
and they still work great. This is the only kind I use, I can not 
stand a watch on my wrist, they make me break out. they all ways 
have, and I suppose, they all ways will.

Fred Waldrop