Channel 73 is 161.205 and as I mentioned previously I have never heard any activity on that frequency, not just for BNSF/Barstow but along any railroad at any time from when I started monitoring railroad frequencies. The BNSF/Barstow yard has a private security company keeping an eye on their yard, I have had two dealings with these guys, first on 10/16/96 and more recently on 11/11/21, this second time was between USMC Logistics Base and Daggett, I suspect they spotted me photographing trains from the dirt road parallel with the tracks on one of their cameras and dispatched security, since this is a private company I thought they may be using a business frequency which prompted the question on my original post. It has crossed my mind that they use other ways to communicate besides regular RF. When I go out photographing trains I only have my amateur radios to monitor railroad frequencies, my mobile Yaesu memory channels 1 thru 100 are AAR frequencies, this radio has dual display so I can scan on the left side and VFO the right side. If this security company does use RF whether it's railroad or business I thought someone out here may know.