Can I use it with my RasPi? Also, what does 10-20VA mean?
I've had my RasPi for two days and initially I started with a brick power supply rated 5V 700 mA ad originally used as a battery charger: it has a LED that is green without load and becomes yellow then read as the current draw increases. The net result using that power supply was the ethernet port not working and the charger became hot and smelly after half a hour of playing with the RasPI.
I've found a wall power supply rated 5V/1A, originally for a powered USB hub, and bought an usb PCB connector and a 2200 uF/10V capacitor. I beheaded the original connector and soldered the pcb connector and the capacitor on the output lead.
Worked like a charm this evening.
The short story is: the raspberry Pi likes well regulated and filtered power supplies, capable to put a steady 5V/1A output.