> I'm not at all familiar with the SteppIR design, but I've
Nor am I, but I have many years working with process control and positioners
prior to moving into computer science.
Which brings up my question: How does the system know the motors have moved
the tape/elements to the proper length? Hopefully they don't just count the
pulses to the motors.
> done tons of control systems over long distances myself. One
> thing that can happen is a ground loop between the tower
> ground and the house ground if anything in the control line
> system is grounded at both the house and the tower. Normally
> the coaxial lines provide a low enough impedance path to
> prevent significant potential from the different earthing
> points, but problems can happen. I'm assuming the coax is
> grounded well for dc at the tower and the shack ground.
> Also some control systems don't like a capacitive load. I
> don't have a high level of confidence when dealing with
> digital engineers and long cables. Are there sensitive leads
> that need to be in a different cable away from motor leads?
> Is there something like a crowbar that shuts the system off
> on overvoltage? Is there a diode or gate protection in a
> chip that dumps a transient from control or motor leads back
> into the supply and somehow crowbars it?
> I'd look at the control lines with a triggered or better yet
> a storage scope for transients. See what you got for spikes.
> 73 Tom
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