WHILE EN ROUTE, THE TRANSPONDER WAS INOP & THE PLT LOST RADIO CONTACT WITH ARTCC 2 TIMES. AS HE APCHD THE DESTN (SANTA FE), INSTRUCTIONS WERE RELAYED VIA ANOTHER ACFT. WHEN ASKED WHAT TYPE APCH HE WANTED, THE PLT RESPONDED, 'WELL IF THEY CAN GET ME LOWER, BELOW IT, I'LL CANCEL.' A MESSAGE WAS THEN RELAYED THAT ARTCC COULD NOT CLEAR HIM BELOW HIS ALT OF 13,000'. SHORTLY THEREAFTER, THE PLT RADIOED HE HAD CROSSED OVER THE VOR & WAS DSCNDG TO 8000'. THE CONTROLLER TRIED 2 TIMES TO CONTACT HIM DIRECTLY, THEN RELAYED A MESSAGE TO SQUAWK 1200 (VFR CODE), THAT RADAR SVC WAS TERMINATED & TO CALLSANTE FE TOWER. THE PLT DID NOT CONTACT THE TOWER NOR LAND AT THE ARPT. ON 10/10/84, A SEARCH WAS INITIATED & THE ACFT WAS FOUND WERE IT HAD CRASHED NEAR THOMPSON PEAK AT APRX THE 9400' LEVEL. THIS LOCATION WAS APRX 15 MI ENE OF THE ARPT &THE VOR. RADAR DATA SHOWED THE DSCNT WAS STARTED APRX 12 MI EAST OF THE VOR, THEN THE ACFT TURNED NORTH TWD THE CRASH SITE. THE ACFT HAD PREV 'RADIO PROBLEMS.' NO LOGBOOK ENTRY FND FOR VOR CHK. PLT LAST LOGGED INTRUMENT TIME ON 4/17/82.