Pine Creek was not only a mining town but the end of the Darwin train line south, built in 1887-1889 The southern extension to Katherine was built in 1914-1917. The tower before you is one of two home signal towers built to control trains entering the rail yards of Pine Creek and would have been constructed at this time. The other tower is on the northern end of the Pine Creek Rail yards.
You are looking for a magnetic micro.
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