I'm a new General and been hearing different phonetics on the air. Some ops use the standard NATO alphabet (Alpha, Bravo, Charlie), others use custom words like "America Boston Canada." When should I stick to NATO vs. use alternatives?

Also noticed DX stations sometimes switch between different phonetic sets during the same QSO. What's the strategy behind this?

The ITU adopted the NATO phonetic alphabet developed in the 1950s to be intelligible and pronounceable, and is generally understood by all amateur radio operators around the world. When you say "Whiskey Seven Alpha Bravo Charlie," they copy perfectly. Use the standard—it works from Albania to Zimbabwe. For DX work, always start with NATO - it's what they're expecting to hear.

If the other operator is having trouble picking my callsign out of the noise, it sometimes helps to switch phonetic alphabets. Sometimes one or the other sound just happens to get through better or is more recognizable by the other radio operator (especially if English is not their primary language). I use "Kilo Zero Norway Radio" instead of "November" sometimes - one less syllable.

A callsign such as WØLPR might be "Whiskey Zero Long Playing Radio." Certainly easy to remember but if you use these phonetics on the air under marginal conditions, you'll probably just confuse the operator on the other end. Learned this the hard way during my first contest when nobody could copy my creative phonetics!