The ACA issued a public warning that a signal
from the warship was overloading hand-held controllers used
for door openers. Many garage doors just would
not open when the ship berthed at dock.
The ACA said the hand-held controllers used
the same frequency as the ship's transmitter - in a spectrum
allocation that is shared by defence services
and class licensed low interference potential devices.
Australian defence installations generally
avoid those frequencies but changing the frequency of the system on
the US ship is too complex to do in a few
days during its visit.
When the USS Carl Vinson left Hobart, and the operation of garage doors returned to normal.
Bryan Ackerly, VK3YNG.