This fox is suffering with mange and will die within four months if left untreated. Meanwhile spreading the disease to other animals including your pet dog.
Feeding the fox will not cure the problem but will prolong the agony.
I have tested these fox repellents and by following the instructions on the pack they really do work in their different ways to deter and repel foxes.
Scoot, described in more detail below, works by mimicking the scent of foxes, cats and dogs ignore it.
The other two methods a motion activated water spray and the ultrasonic pest repellent with strobe light, again more detail below, work by scaring foxes away from your garden, but will also scare
Motion Activated Animal Deterrent
Ultrasonic Pest Repeller with Strobe Light.