Re: To use magnets instead of a spring in chrom design

["Vern Smith" <jevern@xxxxxxx>]

 ----- Original Message ----- 
 From: "Douglas Tate" <douglas.tate@xxxxxxxxxxxxxx>
 To: "Harp-L" <harp-l@xxxxxxxxxx>
 Sent: Friday, April 30, 2004 6:24 PM
 Subject: Re: To use magnets instead of a spring in chrom design


 > A serious reply to the magnet bit with semiserious additives.
 >
 > The prob with any type of electrically operated switch is that when you
 say
 > go, it goes.  At the same speed every time. When you let go the same
thing
 > happens. There is no subtlety to it... there are different ways to
 approach
 > the pushing of the button, one doesn't want it rushing down that little
 > slide slot like an ICBM anxious to spoil someone's day!

 I think that Nidalap was referring to permanent magnets and the above
 paragraph seems to refer to a magnetic solenoid.

  However, I claim to have solved the problems mentioned above in the foot
 pedal that Cynthia Dusel-Bacon used at last year's SPAH03.  It uses an
 external spring to partially oppose the spring in the harp and an R-C
 network to avoid the "clack" when the solenoid armature slams into its
stop.
 It also has three adjustments that need to be tweaked whenever the model of
 chromatic harp changes. It works well, but is bulky and complex. The
details
 are technical but I'll describe them offline to anyone interested.

 Vern

 Visit my harmonica website: www.hands-free-chromatic.7p.com