Icom IC-720A QSL Card 1989: KU7F to WBXP Liberia DX Ham SSB Radio Contact

That "57" indicates a signal that was readable, with moderate strength, and a good, clear tone. The lower left corner bears the operator's signature as "OP.". Turn the card over, and the back is largely blank, save for WBXP's call sign, neatly rendered in blue ink.

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