Minecraft wiki entry for Dropper, associated text: When activated, a dropper waits 2 redstone ticks (4 game ticks, or 0.2 seconds barring lag) and then ejects one item from its inventory. The dropper does not continue to eject items while activated — ejection occurs only on the initial activation (the rising edge of an input signal). To eject multiple items, repeatedly activate the dropper with a clock circuit.