It's a transmitter, a radio for speaking to God.
Belloq: How odd that it should end this way for us after so many stimulating encounters. I almost regret it. Where shall I find a new adversary so close to my own level?Indiana: Try the local sewer.
Adios, Satipo...
This site also demonstrates one of the great dangers of archaeology; not to life and limb, although that does sometimes take place. I'm talking about folklore.