There were two on Northwestern Pacific. One was up on the north end between South Park and Eureka, visible from US 101. The other was at mp 48.8, about a half mile from my home. The daily entertainment from the NWP was listening for the train crews calling out the hotbox detector.

Engineer would announce the detector. Some would say it the right way, "NWP 2594 West, hotbox detector." Some would just say, "SCANNER."

Conductor or rear man in the caboose would go to the back platform and watch for the display after the train had passed. "All clear on the hotbox detector, NWP 2594 West, out."

On the occasions when the crew would let me ride along with them in the caboose, they'd let me do the honors on the radio. Those were far more innocent times. Everyone involved has by now retired and most have gone to the Great Northwestern Pacific in the sky.