ETX TECHNICAL TIPS Last updated: 28 March 2001

FOCUS KNOB TIP

Subject:	Easy way to remove 'focus knob jitter'
Sent:	Tuesday, March 27, 2001 19:56:55
From:	dcloukota@juno.com (Douglas C Loukota)
Ever since I've had an ETX125 I've been going to build an motorized
focus control.  One thing leads to another, and I haven't gotten to it
yet. Last night , out of 'focusing jitter' frustration, I hit a very
simple and CHEAP solution.  So for what it's worth, here it is. 
Sometimes the simple ideas work the best. Remember "KISS", Keep It
Simple Stupid.

I found a piece of light open cell sponge rubber, the type that a PC
card might be packaged between.  Its about one inch thick if you don't
count the bumps.  Cut a circle about 1.5 in diameter of small enough not
to hit the other parts of the scope.  Make a small hole in the center
about .25 in dia.  Slip the ring over the existing focus knob and you
have built a vibration absorbing knob.  With a light touch it really
works.

Doug

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