Serial TRHs at the Ah (1,2,3,5,6), C and M towers report their serial numbers in every data record, and so they can be displayed in real-time with rserial, or from the data archive with data_dump. At the Ah sites, sensor id N,40 is the 0.5m TRH and N,50 is the 2m TRH, where N is the station number:
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