1983-1985: Magnavox Odyssey 3 Command Center, Sega SG-1000 Mk II
During this period, Sega--which would go on to become a major player in the home-console market--first made its presence felt.
1983: Magnavox Odyssey 3 Command Center
Previewed at the 1983 Consumer Electronic Show (CES), the Odyssey 3 Command Center held out the promise of an improved keyboard, a built-in joystick holder, a voice synthesizer, and a 300-baud modem. It was never released. Nevertheless, I stumbled upon this promotional ad for it. (The analog synth soundtrack is kinda catchy.)
1984: Sega Game-1000 Mk II
The original SG-1000 was Sega's first foray into the home-console market. Despite achieving a measure of popularity in Japan, Australia, Italy, and Spain, it never reached U.S. shores. In 1984, Sega launched the 15,000-yen (roughly $125) SG-1000 Mk II, with an improved CPU, a redesigned case, and a detachable keyboard. It remained a stranger to the Americas as well. Not until 1986's Master System did Sega arrive in U.S. homes.