It is hard to get a fox to go into a live trap...you might have better luck with steel trap, if it is not against your laws in your area. Also remember if you use steel trap other animal may get in them(dogs-cats-other pets).
If there is a skunk or possum in the area, your libel to catch it no matter what you use for bait. Tainted meat tends to be a better draw later in the year when food pickens are getting slim and the scent travels better in the cold air. Any of the above may work, or not, depending on the fox. Young of the year fox (which will be large by now) are not as cage trap shy as adults.