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While the CTC system is in full effect along the S.M.A.R.T. corridor, I do believe it is more of a signaling system like B.A.R.T. where the "operator" requests a signal out via a control panel in the cab. But it's probably just a button that sends a request to the dispatch center who then sets the lineup.
Seen here, the cab of S.M.A.R.T. 106 sits patiently for the operator to come to this side, and the signals at MP 17 show ALL RED. They will wait around for 5 or so minutes before departing Downtown San Rafael, CA.
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