Ok Mate it sound like its a standard SW Radio you have there?
The AM SW Band is the one you Need it 1621-29999 khz or 1.621-29.999 mhZ so thats the Band you need to use.
Give it a Try!
You can try am and THE sidebands(usb ssb lsb) to see if theres anything out there.
6.541MHZ or 6541khz should have plenty of Traffic on it But you may be out of the Skip Range and in a shadow of no reception. Try and get a PCA chart they have all the relevant frequencies on it.
You mayneed to try someones Pacific HF Freqs for an Airline or Other Countries. Maybe secured with SELCAL so you may be unable to here it.
Sheep