JAMMED SIGNALS: Manuel A. Cabranes, owner of KWNK (K-WINK, 670 on your AM dial), wrote to complain that our drive-time radio compendium last week missed his Simi Valley adult-comtemporary/sportsy station. KWNK also carries Howard Cosel's "Speaking of Sports," plus Dallas Cowboy and Stanford football, Pepperdine University basketball and the Indy 500 auto race. . . . KNTF--whose modern country sounds serve Orange, San Bernardino and Riverside counties--was also left out, but it shares the same FM frequency as KFOX (93.5) and therefore can't be picked up west of Santa Ana. . . . And KKGO's Saul Levine was miffed that his jazz station's listing didn't mention that KKGO--a regular radio Super Station--is satellited around the country to almost 3 million homes. He also wished we'd given jazz--"America's greatest original art form"--a separate category, like classical music.