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allowing a pulse to be delivered. When it is disarmed the contactors open, breaking the
connection between the TMS unit and the coil. By arming the TMS right before
delivering a pulse, and then disarming it before the next image acquisition, we were
able to eliminate the noise seen in figure 6. In figure 8 we again scanned a phantom
while delivering TMS pulses of increasing strength in between each image acquisition;
however this time we used the modified coil control box and disconnected the TMS coil
during image acquisitions. As you can see from the time series, the noise is effectively
eliminated.
Figure 7 The coil control box opened to show the industrial contactors. The contactors act as a switch,
connecting or disconnecting the TMS coil from the rest of the system at both the positive and negative
leads.