Mark Eylers showed me a mini 75 watt power inverter which he bought at a supermarket in France for 17 Euro. Made in China, it converts 12 volts DC into 220 volts AC. Perfect for recharging equipment on the go when you don't have a dedicated 12 volt charger, but do have the mains adaptor. Other inverters are mentioned here in this excellent article, which seem powerful enough to run a small radio station - though considerably larger. Have not seen the Krueger brand in the Netherlands.
