Imagine an immensely underpowered but bulky Nintendo Game Boy sporting some (roughly a dozen, actually) really basic games and you just imagined the amazing Milton Bradley Microvision. Amazing? But of course, as Microvision was the first ever handheld console to feature cartridge-based gaming all the way back in 1979. According to the Handheld Museum:
This system is a cool little cartridge based handheld game designed by Jay Smith (of Vectrex fame), it's kind of a VERY low-quality Gameboy (with a 16 x 16 LCD screen). There are two variations of the machine with regards to the batteries: The first version allowed for two batteries (although I believe it would still work with one), than later it noticed that the machine would work well with one battery, so the place where the second battery would go was labelled 'spare battery storage,' and the electrical contacts where removed. Interesting trivia: the console itself is nothing more than controls, LCD panel and a controller chip for the LCD panel. Each cartridge contains the microprocessor, which happens to have a small amount of ROM space on it that MB loaded the game code onto.
Web resources on the MB Microvision:
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