stone_sounds = {}
stone_sounds.footstep = {name = "stone_walk", gain = 1.0}
stone_sounds.dug = {name = "stone_break", gain = 1.0}
stone_sounds.place = {name = "block_place", gain = 1.0}
glass_sounds = {}
glass_sounds.footstep = {name = "glass_walk", gain = 1.0}
glass_sounds.dug = {name = "glass_break", gain = 1.0}
glass_sounds.place = {name = "block_place", gain = 1.0}
wood_sounds = {}
wood_sounds.footstep = {name = "wood_walk", gain = 1.0}
wood_sounds.dug = {name = "wood_break", gain = 1.0}
wood_sounds.place = {name = "block_place", gain = 1.0}
minetest.register_node(
    "portalgun:powerballtarget",
    {
        description = "Power ball target",
        tiles = {"portalgun_powerballstarget.png"},
        groups = {mesecon = 2, cracky = 2},
        mesecons = {receptor = {state = "off"}},
        sounds = stone_sounds,
        is_ground_content = false,
        on_timer = function(pos, elapsed)
            mesecon.receptor_off(pos)
            return false
        end
    }
)