For this particular Chama-Antonito-Chama roundtrip 484 was carrying a homemade hooter whistle.
(Maybe Earl can fill in the blanks) Supposedly, these were the only two days, ever, that this contraption was used, as it sounded so horrid that after the train got back to Chama they killed the 484 to exchange whistles.
I have cassette recording of it, but alas, my cassette player gave up the ghost some time ago.
Hmm, I DO have an old Walkman laying around, maybe sometime I'll try hooking it up to my edit system and then I can post the sounds of the fool thing.