SMA HAS FALSE LOC SIGNAL; DSNDS BELOW FINAL APCH FIX XING ALT.

Narrative

FLT FROM YTZ TO CAK IN IMC OVER ENTIRE RTE; UNEVENTFUL UNTIL INBOUND FROM APPROX 18 MI OUT AND ON LOC; CAK RWY 23. CLRED FOR ILS 23 BY APCH AND DSNDED TO 3200 FT (MSL); AWAITING XING OM TO DSND TO MDA. HEARD OM AUDIO CLRLY (FRONT SEAT; NON-PLT PAX HEARD ALSO; ASKED WHAT THE BEEPING TONE MEANT) -- CONFIRMED ON HIGH SENSITIVITY. NO OM LIGHT INDICATION. SIGNAL INCREASED THEN DECREASED; AS IF PASSAGE OVER MARKER. AT THIS TIME; APCH HANDED ME OFF TO TWR. BELIEVING I HAD CROSSED THE OM; BEGAN DSCNT TO MDA. NO GS RECEPTION. CROSSED TRUE OM THEREAFTER; AURAL AND LIGHT INDICATION; ALT 2200 FT MSL; 1000 FT BELOW FINAL APCH FIX XING ALT. RPTED RECEIVING FALSE OM TO TWR BY PHONE AFTER LNDG. RESULT: NORMAL LNDG; NO MISHAP. COMMENT/ACTION: WILL HAVE ILS/MKB ELECTRONICS CHKED IN ACFT. ARPT WILL CHK ITS ILS EQUIP -- THEY HAVE HAD RPTS OF FALSE OM ON ILS 19; BUT THIS IS THE FIRST TIME ON ILS 23. IN FUTURE; IF UNCERTAIN OF POS (LIGHT BUT NO AURAL OR VISE VERSA; REMAIN AT ALT UNTIL SURE (CHK VIA VOR CROSS RADIAL OR RADAR) OR GO MISSED APCH; RATHER THAN GO BELOW A SEGMENT MINIMUM ALT UNTIL SURE OF BEING INSIDE FINAL APCH FIX. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES HE HAD ACFT CHKED AND A LOOSE ANTENNA COUPLING WAS DISCOVERED. HE BELIEVES IT WAS HIS EQUIP; NOT AKRON ILS THAT WAS THE PROB. GS WENT OUT AT SAME TIME; BUT WHEN HE TALKED TO TWR THEY SAID GS WAS WORKING FINE. DOES NOT KNOW IF AKRON FOLLOWED UP WITH A CHK OF ANY KIND.