Testing showed that the new machine could be run with the wobble largely gone.
However, it can still have wobble if adjustments are made so that it will.
If that is done, then results are pretty much the same as were with
testbed 1 here. However, the whole
idea behind the new testbed was to see what happens without wobble.
The result was that a new set of spikes that turned out to originate from
interference from the new motor and that there was
nothing resulting from the movement of the
wires through the grids.
In all the oscilloscope shots below, the main wave is the 60Hz sine wave
coming from household wiring.
Channel 1 (top trace on pictures below) is from
right, disk-facing grid and the corresponding back grid.
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Channel 2 (bottom trace on pictures below) is with
the ground connection of the probe connected to ground and the
other connection connected to an xacto knife blade.
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The spikes. As the above pictures show, the top
trace is from the small machine, and the bottom trace is from a ground
wire and an xacto knife. Clearly, since both show spikes, the spikes are
from interference from the motor. The next two pictures further illustrate
this since the timing of the spikes does not match the timing of the disk
rotation.
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The rate for the spikes is measured here as 396.8Hz.
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At the time that these traces were captured, the
phototachometer indicated that the disk was rotating at 1008RPM. This
means that the rate of the wires passing the grids being used for
measuring is 336Hz
[(1008rotations/minute / 60seconds/minute) * 20wires/rotation =
336wires/second]. In this picture, the scope's cursors (dotted vertical lines)
have been positioned to show where the spikes would have to be for 336Hz
(337.8Hz in the picture since that's the closest the scope could to for this
resolution).
Clearly the cursor that is to the right of center shows that the center
spike is nowhere near where it would be if the spikes were coming from the
wires.
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The conclusion is that there is nothing useful coming from this small
machine testbed with the setup so far.
