What is the fine-grained topic of the following text: Buck Night: KC9NTT, WA9ACI, W9IXG, K9EMG, KC9MGB, KC9MDA, KB9KVA, K9ITW, Ted K9IMM (winner of the buck), W9CAR, KC9MWP, K9MA, W9DGI, KF9AQ, NK9U, K9APW, K9ITW, WB9BRF, AD9X, KC9OHU, KB9ZQZ, Betsy WN9GOC (winner of the key). Only return the topic.
Amateur Radio Call Signs Event with Prize Winners