Family Computer Network System/TV-NET (partially found ROM and peripherals of telecommunication service for Famicom; 1987-1991) - The Lost Media Wiki
Almost done collecting all the accessories for the Famicom. Pictured is the Famicom base unit, Disk Drive, Network Modem, Keyboard, 3D Glasses, Data Recorder, ROB the Robot (w/ Stack Up and Gyromite),
A Brief History Of Nintendo's Home Hardware Add-Ons | Nintendo Life
Famicom Modem and NES Teleplay Modem - Feature - Nintendo World Report