Probably easier to use this one at home:
MEGA-SONIC CAT DOG & FOX DETERRENT REPELLER SCARER REPELLENT | eBay
and this one for example, where there is no electricity source available:
Scoot Fox Repellent | Fox Deterrent | Fox Repeller
We get the odd fox but we're on good terms... feed it some lemons or green apples now and then and it stays away. Usually a few 20-30 ft from the driveway and I think its convinced the food source and terriority is further away now. I'm not a fox expert though but I think one of those websites had a 'fox helpline' for advice and tips!
Our problem here is cats, one got under the bonnet the other day and I started it up and it ran out!!