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Re: No sound-inputs but sound recording FMIT




On Sunday 05 March 2017 17:16:36 John Hasler wrote:

> Gene Heskett writes:
> > Very simple. With the glaring exception of the modern AC induction
> > motor that in 99% of the stuff we buy, ANY other generator can also
> > be used as a motor...
>
> Induction motors can function as generators.  You just need to connect
> them to an appropriate AC source and drive them above synchronous
> speed.
>
Yes, there is that exception, they need an excitation current, true, but 
in that case they make excellent brakes as they don't like spinning 
above synchronous any better than they like running below it.  And with 
enough dc current you can come pretty close to stopping them dead in 
their tracks. Certainly within one revolution.  But the armature is 
soft, and its not possible to maintain the magnetic field from its 
shorted turns armature long enough to extract any output power from it 
for more than a few milliseconds.

> GiaThnYgeia writes:
> > So, are you saying the standard motherboard beeper/speaker (the one
> > that beeps when you hit too many keys at once or that bios is
> > telling you I am booting up ... any minute now beeeeepp) is a
> > microphone that feeds sound back into the system and mysteriously
> > debian is allowing it to be recognized as an input device.
>
> No, due to the absence of all the other parts needed deliver any
> signals generated by the speaker back to the computer (not to mention
> that it would make a very poor microphone).


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>