cats in the garden

[munchie63]

this must have come up before, but I struggled to find anything.

has anyone had any success in deterring cats from using their garden as a litter tray.
next doors cats driving me up the wall at the moment.
I've 2 kids, so need to stop this, but want to do it without resorting to hurting the cat.
anyone used one of those sonic devices, or any other suggestions.

[daisyblack]

Sorry that link is cat repeller

they're really good value for money too