I beleive they are 220mHz antennas for PTC. Locally, Norfolk Southern Built a new Wye. The Wye complex is a form of CTC, but the rest of the line is ABS and Track Warrent. Since these CTC signals are absolute, then if a train passes a restricting indication, it stops the train (in theory).
Im not seeing any new licenses in the db for the ptc antennas here. Is that going to license by rule? Anyone know. I might go out with the signal stalker to find what 220the freq.s its transmitting on.
If there is a base antenna, Im sure there is a radio connected to it. I am equally sure that the base radio is housed inside an equipment shed next to the CP, hence the term wayside base. It is a base radio next to the right-of-way.
Eventually, as PTC is developed, the wayside base will start to transmit whatever data it needs to transmit. At that time I will do a sweep with the scanner to try to find what frequencies the base transmitter is transmitting on.