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<div class="moz-cite-prefix">All,<br>
I have been taking apart those old SCSI-3 harddisks (I dropped
about 100 of off over at Splat*Space) and it is quite easy, even
maintaining the connector pigtails. The only thing is, the motor
bearing is machined into the case itself. That means cutting the
(aluminum) case to a manageable size -- not an easy task at the
moment.<br>
<br>
By the way, Elektor magazine specifically has an article with a
circuit for driving these motors. The input to the circuit is
servo drive signals like those from an radio-controlled receiver.
And there are standard library functions for that for all of the
microcontroller boards (Launchpad, Arduino, R-Pi/Python, etc).
You can use an RC throttle to control the speed of the motor --
and through component selection select the maximum speed of a
motor.<br>
<br>
On 07/24/2014 11:02 AM, Pete Soper wrote:<br>
</div>
<blockquote cite="mid:53D12018.1060002@soper.us" type="cite">One
more alternative that just occurred to me: identify and isolate
the controller chip in a drive or fan, look up it's specs and
patch some kind of control into it while it's wired to your motor.
<br>
<br>
And I simply failed to include another, easier alternative if
something off the shelf would do. There are RC model-related PWM
controllers that you can simply connect to your motor and they
will just immediately work. I think I subconsciously filtered this
out by figuring you guys have the usual academic budgeting levels
for a project like this. :-)
<br>
<br>
-Pete
<br>
<br>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="80">--
Scott G. Hall
Raleigh, NC, USA
<a class="moz-txt-link-abbreviated" href="mailto:ScottGHall1@GMail.Com">ScottGHall1@GMail.Com</a>
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