Mountain Echo Recorder

Mountain Echo Recorder is a Device Gadget from the Doraemon Franchise. The device is shaped as a 3 peaked mountain. The color of the gadget itself is green and is probably twice as big as Nobita's palm. It has 3 button below a screen(?). Apparently, the gadget works by just placing it inside a building. Tne gadget was used to echo the attacking sounds and laser attacks of the raiding bots. To imitate a retaliatory attack from Humans, so it won't raise suspicion. Even though the gadget did what it supposed to do. But at the end, the gadget was discovered by the robots.