Big, beautiful, and silver… the first computers in the Color Computer series are known today as CoCo1’s, and cover a number of variants. There are at least four major NTSC motherboard versions that were released. These motherboard types are generally referred to by a letter that appears at the end of Tandy’s board numbering scheme on these machines.
Late model CoCo1
‘C’, ‘D’, ‘E’, and ‘F’ boards may be encountered in circulation. The ‘C’ boards are purported to be very rare, but the other types show up in machines available on eBay and other sources regularly.
‘F’ board CoCo1 motherboard
‘F’ board variants (the last type to be produced) are easily upgradable to 64K. Earlier types can be upgraded with varying degrees of difficulty.