Monitoring of standard train frequencies in Kensington MD (the CSX Metropolitan Subdivision, also called "BA"), mostly the 160.23 Mhz standard road frequency, the dispatcher channels, and the 452/457 Mhz range Distributed Power Unit (DPU) automated signaling (sounds like a gargling tone).  Commuter MARC trains also run here on weekdays.  The scanner's range is rather limited, so it only picks up signals within a few miles.   It can usually pickup the defect detector at the 11.6 mile marker.   Here's the list of the most interesting frequencies scanned:

The Broadcastify feed typically seems to be delayed by several minutes.  The scanner for this feed is a Bearcat 125AT with 5/8 wave omnidirectional antenna feeding to a Raspberry Pi 4.