FLC OF CPR SMT ACFT DEVIATED FROM ASSIGNED TRACK DUE TO SETTING THE WRONG NAVAID FREQ.

Narrative

CTR ADVISED US; UPON PASSING LAKE HENRY VOR (LHY); WE WERE APPROX 6 MI N OF V-58; OUR ASSIGNED AIRWAY. CTR REQUESTED OUR OUTBOUND RADIAL FROM LHY TO WHICH I REPLIED 088 DEGS. WE IMMEDIATELY CORRECTED TO THE R; HOWEVER; WE WERE STILL NOT SURE WHY OUR #1 NAV WAS SHOWING US CTRED ON THE AIRWAY. I ACTUALLY LOOKED AT THE VOR FREQ SET IN #1 NAV 3 TIMES BEFORE I REALIZED IT WAS TUNED TO WILLIAMSPORT (IPT) VOR! PRIOR TO DISCOVERING THE ABOVE; WE HAD TUNED #2 NAV TO LHY VOR WHEN CTR ADVISED US WE WERE ON V-58 OUR #2 NAV; WHICH WAS PROPERLY SET; INDICATED WE WERE S OF THE AIRWAY! ONCE LHY VOR WAS PROPERLY TUNED #1 IDENTED ON #1 VOR WE DID SHOW PROPER AIRWAY LOCATION. THE ACFT VOR CHK BOOK WAS ON BOARD AND CURRENT. ON THE SAME LEG OF THE FLT WHILE WORKING OTHER VOR FREQS; BOTH NAV UNITS WERE IN AGREEMENT REGARDING OUR POS. WE ALSO CONDUCTED A GND VOT CHK THE SAME DAY WITH BOTH NAV UNITS SHOWING PROPER ALIGNMENT. PRIOR TO CTR CALLING OUR POS; WE HAD BEEN IN THE PROCESS OF COMPUTING ENG PERFORMANCE AND TRUE AIRSPD CALCULATIONS. AFTER GIVING THE SITUATION MUCH THOUGHT; IN THE FUTURE I WILL PROPERLY SEE WHAT I LOOK AT; IDENT THE NAV STATION; AND PAY MUCH CLOSER ATTN TO THE NAV PROCESS; ESPECIALLY WHEN IN CLOSE PROX TO NAV STATIONS. ALTHOUGH THERE WERE NO TFC CONFLICTIONS; THESE ARE THE TYPES OF MISTAKES THAT CAN CAUSE THOSE SITUATIONS TO ARISE.