RAM Adapter The disk system attaches to the Famicom using a modified cartridge known as the RAM Adapter (HVC-023). Also -- an "experiment". This week we talk about why the Famicom Disk System is able to use six AA batteries, and whether or not the battery tray is a viable solution for your Famicom gaming needs. The Disk System is capable of running on six C-cell batteries or the supplied AC adapter, which is 9V DC, 400mA, with center negative polarity.