CREATE TABLE table_31966 ("Calls" TEXT, "Frequency" TEXT, "Branding" TEXT, "Format" TEXT, "Timeslot" TEXT, "Group owner" TEXT)

Tell me the branding for frequency of 680 khz
SELECT "Branding" FROM table_31966 WHERE "Frequency" = '680 khz'
SELECT "Branding" FROM "table_31966" WHERE "Frequency" = '680 khz'