A C172 PLT; USING A JUST-PUBLISHED NEW CTAF FREQ EXPERIENCED AN NMAC AT C59 WITH A BONANZA USING THE OLD FREQ.

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THE CHICAGO SECTIONAL LISTS AN INCORRECT CTAF FOR C59. I WAS ON A SUNDAY AFTERNOON PLEASURE FLT; GYY-C59-GYY. THE WX WAS CAVU. BEFORE DEP FROM GYY; I GOT A PHONE BRIEFING FROM KANKAKEE FSS. THE BRIEFER SAID HE HAD NO NOTAMS FOR C59; BUT A 'NOTE IN HIS FILE' SAID THAT THE CTAF FOR C59 WAS 122.9. THE SECTIONAL SAYS 122.7. THE NAV DATABASE IN MY LORAN SAYS 122.9. APCHING C59; I USED 122.9 TO REQUEST 'WINDS AND ACTIVE.' NO RESPONSE. FLEW OVER FIELD AT 1500 FT AGL; SAW NO ACTIVITY; NO INDICATION OF ACTIVE RWY. BASED ON NEARBY SMOKE DRIFT; MY GND SPD AND CRAB ANGLE; I ESTIMATED WINDS OF 300 DEGS AT 5 KTS. THIS WAS CONSISTENT WITH NEARBY ATIS'S AND OTHER ARPTS LNDG ON RWY 36. I FLEW 2 TOUCH-AND-GOES ON RWY 36; USING STANDARD TFC PATTERN; SELF-ANNOUNCING ON 122.9. AS I DEPARTED RWY 36; AFTER MY SECOND TOUCH-AND-GO; A BEECHCRAFT BONANZA WAS APCHING TO LAND IN THE OPPOSITE DIRECTION. WE EACH VEERED TO OUR RESPECTIVE R'S; MISSING BY 100-200 FT. AFTER CLBING AND LEVELING OFF; I SWITCHED TO 122.7 AND (SURE ENOUGH) THE BONANZA WAS SELF-ANNOUNCING ON THAT FREQ. AT MY SUGGESTION; HE SWITCHED TO 122.9. LATER; I HEARD OTHER TFC USING 122.9 FOR CTAF AT C59. ALSO; I SUSPECT THE BONANZA WAS FLYING A STRAIGHT-IN PRACTICE NDB APCH TO RWY 18. HE DID NOT FLY A STANDARD TFC PATTERN. THIS NEAR MISS WAS CAUSED BY: 1) CONFUSION AS TO THE APPROPRIATE CTAF FOR C59. 2) THE BONANZA PLT'S FAILURE TO FLY A STANDARD TFC PATTERN; CONTINUING HIS STRAIGHT-IN APCH INTO THE ATA. RECOMMENDATIONS: 1) MAKE THE EFFECTIVE DATE OF CTAF FREQS COINCIDE WITH THE ISSUANCE OF THE RELATED SECTIONALS. 2) OR; AS A WEAK SUBSTITUTE; ISSUE A NOTAM THAT REMAINS EFFECTIVE UNTIL THE NEXT SECTIONAL IS ISSUED; REFLECTING THE NEW CTAF. 3) CONTINUE EMPHASIZING THE IMPORTANCE OF STANDARD TFC PATTERNS.