The drive belt inside the Nintendo Disk System unit had dried out and deteriorated after 40 years. I replaced the drive belt with a new one. During the replacement, the gears would turn on their own, causing the head to be out of position, so I also adjusted the head to its proper position. I tested it with Capcom's Gun.Smoke up to the second stage. Also, the RAM adapter that plugs into the Famicom unit should not be pushed all the way in; instead, insert it with a slight gap to avoid poor contact. Please insert it with a slight gap, like a Famicom cartridge. Rare Section Z (A and B sides) included. This is a Disk System, a peripheral for the Nintendo Famicom. Back then, most cartridges were less than 1 megabyte (like Donkey Kong and Star Force), but the Disk System was positioned as the way to go for games with 1 megabyte of capacity. However, shortly after the Disk System was released, games exceeding 1 megabyte, such as Commando, were released on cartridges one after another, seemingly questioning the Disk System's significance. From then on, it became more like it was only for games up to 1 megabyte. Junk, Family Computer, FC, DS