How do you tune a samsung tv that has come from New Zealand (tuned into NZ tv) to Australian free to air channels?

Are you trying to get over the air channels? IF you are does your TV have the digital tuner on analog? TV went digital and if you have an analog tuner will need either e new TV or converter box.

You can still use an Analog Device if you have an Analog to digital Converter box.

not a answer but have a question. ..
we bought this Soniq tv from Aus but we can't search channel here in samoa . how can I solve this problem pls?

for tv channel it tune as you select channel. just select air or cable channel.

Set the TV to cable tuning mode and use that channel 73. You have it set for air now so it can only tune to channel 69.

tuning nec fs5185

You will need to have a tuner fitted which will work with the local frequencies. Is New Zealnd NTSC?

the convergence board has nothing to do with tuning of tv, the convergence board put three colour gun (red, green, blue) to work with each other, else you get three image, of red , green,  blue or mixture of all as seperate image, the convergence board for american tv and Australian tv is possibly the same what you check to see the board  part number is the same you possibly need to see if the convergence board has got the memory i.c. if that is the case, you need to tune you t.v reset the channel etc good luck.
need more help let me know.