All you need is the power supply that works for the country you are visiting. For the XM, what you are looking for a local vendor of a power supply is a switching power supply, 5 Volts, Amps is between 1.5 and 2.5, plug size 5.5mm outer, 2.1mm inner, with + positive on the inner connector. You don't need to convert the voltage, you need to buy a power supply with the specs I listed (for the XM). Actually, I just looked at both my XM and GX power supplies, and they are switching power supplies, meaning they work on 110V and 220V, and AC 50 and 60 Hz. This means if the country you are visiting has one of these voltages and one of these frequencies, all you need is a plug adapter.
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