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To remove this noise the TMS console will be moved out of the scanner room,
and the penetration panel of the scanner room will have to be rebuilt to include the
Souriau circular connectors that the TMS coil uses, so that a connection for the coil can
be provided without comprising the noise shielding of the scanner room. Additionally
filters will have to be connected in series with the leads of the TMS coil to prevent noise
from outside the scanner room, including the noise generated by the TMS consol, from
being piped in to the room by the coil. Unfortunately filters capable of withstanding the
high currents of the TMS pulse (up to two kiloamps) are extremely large, heavy, and
expensive. Fortunately noise is not an issue while the TMS pulse is being delivered,
since image acquisition is not being performed at that time. As a result we could use
relays to disconnect the filters while the pulse is being delivered, and reconnect them at
all other times. The currents generated in the coil by noise are on the order of hundreds
of milliamps, therefore small and inexpensive filters can be used.