Amen to that.
There seems to be more belief of myths recently in the ham field than before
and I suspect a good part is from AG6K's absolute pathetic nomsense that is
read by the totally uninformed and it becomes doctrine.
Carl
KM1H
----- Original Message -----
From: "Bill Fuqua" <wlfuqu00@uky.edu>
To: "Charles Harpole" <k4vud@hotmail.com>; <amps@contesting.com>; "David
Springer" <dspringer@cfl.rr.com>
Sent: Friday, June 15, 2012 12:49 AM
Subject: Re: [Amps] filament instant heating query
> Myth Busters did an experiment with light bulbs to see how they were
> affected by switching some on and off and others left on.
> Practically no difference.
> I believe this mostly started with light bulbs because when once the
> filament gets so thin at some point due to the evaporation of the
> tungsten the next time you turn it on and you have a surge of current in
> the lamp it burns into. This thin area has a higher resistance
> than the rest of the filament and gets hotter.
> I don' think there is any real rocket science, molecular physics or
> quantum mechanics to it.
> 73
> Bill wa4lav
>
>
> At 03:59 AM 6/15/2012 +0000, Charles Harpole wrote:
>
>>to check on a supposition............
>>
>>
>>
>>It appears possible that the sudden application of voltage to a tube
>>filament causes degradation of the filament.
>>
>>
>>
>>What seems to happen? Is it possible that the very rapid heating of a
>>filament could cause so much quick molecular action (rapid increased
>>bouncing around of the molecules) that the shape of the filament could be
>>changed? A deformed filament could then be too close to other components
>>to cause an arc, perhaps?
>>
>>
>>
>>Or is the action on the atomic level...i.e., does heat change the actions
>>of electrons in an atom?
>>
>>
>>
>>But, maybe the filament rapid heating works just fine, and all of the
>>"slow start" "inrush protection" circuits are a waste?
>>
>>
>>
>>Another inquiring mind wants to know.
>>
>>73,
>>
>>Charles Harpole
>>k4vud@hotmail.com
>>_______________________________________________
>>Amps mailing list
>>Amps@contesting.com
>>http://lists.contesting.com/mailman/listinfo/amps
>
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