[sdiy] damnable digital interface.

Robert Kent hanuman at ccsi.com
Wed Aug 7 06:49:27 CEST 2002

On Fri, 2 Aug 2002, Steve Begin wrote:
> Is there such a thing as a knob that acts like a membrane switch being
> pressed for every x degrees it is turned, and can close another switch
> when it's turned the other way? I've seen volume controls on digital
> amplifiers with knobs that can spin forever and seem like maybe that
> is how they function,  but I'm not really sure.
> It's a bit annoying having to press up 80 times consecutively when
> adjusting the cutoff frequency :)

And Daniel Araya provided this link:


  Coincidentally, I attended a hamfest on Saturday and picked up a
broken Yaesu FT-23R 2-meter transciever which contained this exact
ALPS part (SRBM1L). This part does exactly what you describe.
A full shaft rotation encounters 20 detents. Each detent triggers
one or the other of two momentary contact switches, depending on
direction of rotation. It's very cool.

  Check out the English side of Elfa's site to place an order:
the SRBM1L, stock number 35-884-64, sells for $6.03USD in single

  I am sitting here twiddling the shaft of this thing and deriving
great entertainment from all the creative suggestions offered by
the list. ^_^

--Robert Kent
  hanuman at ccsi.com

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