The 'Y' is usually preceded by a 1 kHz pip, which might be a morse code 'T' But the spacing between it and the 'Y' is about two and a half seconds. If the ID were supposed to be "TY", you would not expect so much space between the two elements. Sometimes, the 'Y' is heard without the preceding pip.
I first heard the 'Y on 23 Apr 2022, but wrote it off as an intermod product generated within my receiver, which was a SDRPlay original RSP1. The RSP1 suffers from HF intermod issues, and I had heard known short broadcasters at various spots on the AM band, so I didn't think too much of hearing the morse code 'Y' at the time.
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