The only radios which can be used legally in Switzerland without a licence are on the PMR 466 MHz waveband.  Unlike some other European countries, where the authorities appear so unconcerned about the unlicensed use of amateur frequencies that 2m radios are widespread, Switzerland has a reputation for enforcing the law in this area.  Stories of popular landing fields being staked out and radios destroyed were in circulation a few years ago, but now that more pilots are flying XC and landing out, offenders may be less easily caught. My impression is that a smaller proportion of Swiss pilots fly with radios, compared with other nationalities, and those that do appear to use the 446 MHz waveband, not 2m.  However, some of the dedicated XC brigade have licences and equipment enabling them to contact the relevant Air Traffic Control to obtain permission to cross certain restricted zones (e.g. Sion TMA).