I checked also and did not find the exact UDC. The logger does not have to correctly calculate your score as the contest sponsor will do that. It does need to accept the 4-digit exchange. RTTYOps WW DX RTTY Contest rules: https://rttyops.com/index.php/contests/cq-rttyops-ww-rtty/15-cq-rttyops-ww-rtty-21. OBJECTIVEFor amateur radio stations worldwide to contact any stations worldwide with use HF bands 160-10m to with RTTY Baudot mode(45 BAUD).The object is to collect year (1900-2021) of issued license of each contacted station and to collect callsign prefixes Scandinavia and Baltic area.
I think there was a thread last year on the RTTY groups.io that said to use the SCC RTTY module for this one.Just took a quick look - couldn't find the UDC for the SCC test, since that contest isn't happening anymore!73 John K3TN