Tampico TB-9
Flight Crew Student
Flight Crew Last 90 Days 39; Flight Crew Total 59; Flight Crew Type 41
Situational Awareness; Communication Breakdown; Training / Qualification
Conflict NMAC; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Landing Without Clearance
Flight Crew Took Evasive Action
Human Factors; Environment - Non Weather Related; Procedure
I joined a left pattern for a full stop landing on runway 19 with what I believed to be the corrected CTAF dialed into Comm 1 in the airplane.  The frequency I had set was incorrect.  I didn't see or hear any other aircraft; but there was one taking off in the opposite direction. We both maneuvered to prevent an accident and no person or property was harmed.I had been with Approach for flight following before switching to what I thought was the CTAF. Before they approved me for frequency change; they informed me that there appeared to be a few planes in the pattern at [the destination].While I had been very vigilant in visually scanning for traffic well before entering the pattern and of course within the pattern; I did not spot or hear from any other aircraft.  However; while on final; I noticed another aircraft that appeared to have taken off from a taxiway in the opposing direction; northbound - appearing to pass around 100 ft below and 300 ft left of my aircraft.  I had chosen runway 19 because what light winds there were favored a landing on that runway.  Despite this alarming surprise of the opposing aircraft; it had passed well clear of me and the runway was clear; so I continued my landing.After taxiing off runway 19 and stopping on the ramp; I found upon reexamining my VFR Sectional chart that I had dialed in the wrong CTAF. I then dialed in the correct frequency; and verified with other traffic over the radio that I was now dialed in to the CTAF.  I then apologized to the other traffic via radio transmission before taxiing to runway 1 for takeoff and departed the pattern to the Northwest.From this I learned:Triple check; then check again; that frequencies I'm dialing in are accurate; using multiple sources if available.If I don't hear from anybody in the pattern; go around the pattern again; and recheck that I am on the correct frequency.If the aircraft's GPS has the ability to lookup frequencies by airport; USE IT.  This way it populates the proper frequency for me (then triple check it).Use ForeFlight; AFDs; or any other resource I have to check accuracy for operations in all phases of flight.  (I was discouraged from using ForeFlight until I had my Private Pilot Certificate.  Now that I have it; I use ForeFlight extensively).
A Socata Pilot reported that when he entered into an uncontrolled airport traffic pattern he did not have the correct frequency dialed into the radio causing a near miss.