A decoding application that loses its CAT link keeps announcing the last
dial frequency it knew, and every decode after that carries a stale
band. Nothing downstream can tell: the entity verdicts, the band filter
and the FT map all believe it. Seen for real — MSHV kept saying 80 m,
and Korea read as a NEW BAND because on 80 m it would have been.
Said, not decided. Taking the rig's band instead would be wrong for
anyone decoding a second receiver on another band, and a warning costs
that setup nothing but a line to read past. Shown only while CAT is
actually connected: an empty band means there is nothing to compare
with, never that the rig is on no band. Opens 0.27.9.