Hornby OO R4901 Network Rail Mk2F 977997 Radio Survey Coach Engineers Yellow

Network Rail have adapted a number of passenger coaches for test train service. These modern coaches are able to travel at speeds compatible with modern trains for routine surveying and infrastructure monitoring.
This coach has been fitted out for radio survey work, testing the radio signals and interference across the network to ensure that cab secure radios will work without interference and locate poor reception areas where an additional repeater transmitter may be required.