[Elecraft] Re: Elecraft Digest, Vol 20, Issue 22 Headphone for hard of hearing

[David A. Belsley]

John:
   Do not cut the speaker cone.  It serves two positioning purposes.   
First it holds the voice coil in place so that it does not rub  
against the magnet or driving coil (depending on the speaker type).   
Second it provides the spring that allows the coil to return to the  
center of its travel from either direction.  Cutting the cone  
material would seriously compromise both of these actions.  I would  
think that an earphone module would serve your purposes quite well.   
They would make some audible sound, but it wouldn't carry very far.

best wishes,

dave belsley, w1euy


On Dec 22, 2005, at 6:41 AM, JohnChanceRead at aol.com wrote:

> I am interested in determining which earphone (or speaker) would  
> have the
> highest physical movement.  I am deaf and intend to read morse by  
> feeling  the
> vibration.  Once I have found the earphone/speaker, I then have  
> another
> problem.  I suspect I will have to find the K2's best audio that  
> fits  the device,
> then I need to nullify its audio output, since I do not want the   
> neighbours to
> be annoyed by loud morse noise.   I partially  understand how a  
> speaker works
> and in order to decrease its audio  output I will have to remove or  
> partially
> remove the paper which joins  the core to the outer body - but will  
> it still
> vibrate ?.  Any  suggestions would be most welcome.
> John G4BOU
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