All Royal Canadian Naval vessels have a unique call sign. This is used in both radio and visual communications. When the Crown Assets and Disposal Corporation was trying to sell HMCS Chaudiere, her call sign was clearly visible painted on the superstructure.
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HMCS Chaudiere Callsign. Nauticapedia.ca. https://nauticapedia.ca/Gallery/HMCSChaudiere_callsign.php