Moog Taurus II Story

william.b.fox wbf at aloft.att.com
Wed Apr 3 18:20:46 CEST 1996


With all of this talk about keyboards, I suppose I ought to share with
you my experiences last night.  While playing Jesus Christ Superstar, my
Taurus II pedals went flakey.  The temporary fix was to use my friend's
pedals with my synth head until the show closed.  Well, Sunday the show
closed, Monday I had a rehearsal, so last night was my first shot at the
big fix.

First, I had to remove the bottom plate in order to remove the top
cover.  Man, this thing is built like a tank!  The frame is solid but
the contacts aren't so robust, though clever.  Each pedal is hinged and
has a spring to return it to its original position.  Near the end of
each pedal (opposite end from your feet!) is a little plastic clip.
These clips have a channel facing a long, narrow circuit board.  This is
where the resister network is located for determining the pitch control
voltage.  At each clip, two coiled spring contacts protrude from the
circuit board, one above the other, vertically.  The lower spring sticks
into a channel in the clip.  The other spring is just above the clip.  So
when you press a pedal, the end with the clip moves up, forcing both
springs up.  The lower spring is the first to touch a stationary metal
contact to establish the pitch voltage.  As the clip raises further, the
upper spring then touches its stationary contact to generate a trigger.
Neat!

+--+
|  |-          <--stationary contact
|  |------     <--coiled spring contact
|  |   +-----+
|  |   |     | <--clip on end of pedal
|  |-  +---+ |
|  |------ | |
|  |   +---+ |                 NOT TO SCALE (Duh!)
|  |   |     |
|  |   |     |
|  | +-+-----+-------------------+
|  | |                           |  <--pedal
|  | +---------------------------+
|  |
|  |
|  |           <--circuit board (end view)
|  |
+--+

On my unit, the low F has a bent lower (pitch) spring on it.  Placing it
back into the clip's channel fixed it... temporarily.  It tends to slip
out easily, especially if you press the pedal to the limits of its
travel or if it jiggles left and right.  This pedal has more jiggle to
it than all the other pedals.  I don't know if I can reduce the left-right
motion and it looks like a terribly big job to remove the pedals to fix
something like this.  I don't relish the thought of doing this on my
basement floor.  Even if I had a work bench, I'd still think twice about
disassembling the pedals.  What I did do was to remove the clip (pops
out) for access to the lower spring and used a needle nose pliers to bend
it back into shape.  After reinstalling the clip and putting the lower
spring into its channel, all seems well and the spring hasn't popped out
of its channel.  We'll see how long this fix lasts.

Bill Fox	wbf at aloft.att.com



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