On this day, the One World Trade Center workers were lowering in to place the very first ring that would support the spire, or antenna, of the tower.

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This makes them easy to set up--no tower or central antenna needed--as well as hard to knock out, since if one device goes down, the others will route around it.

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It leases and manages antenna space on its multi-tenant communications tower sites to wireless service providers and radio and TV broadcast companies.

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The Council on Tall Buildings and Urban Habitat, a Chicago-based organization considered an authority on such records, says an antenna is something simply added to the top of a tower that can be removed.

WSJ: Spire permanently installed on WTC tower

Viewing network shows in eye-popping high def may mean bolting an antenna to your roof and aiming it at the nearest TV tower.

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