TANDY RADIO SHACK
The Color Computer
In July 1980 Radio Shack introduces the TRS-80 Color Computer. 
  • Motorola 6809E CPU
  • 4KB RAM
  • 16 colors display
  • Casette recorder
  • Cartridge slot
  • Plugs into any TV
  • Sells for US$400
  • Model no. 26-3004A
I have two COCO's first model 
  • 1. SN; 03968
  • 2. SN; 02180
The COCO 2
Introduced in 1983, the COCO 2 was basically a refinement of the original (more efficient power supply, higher integration/lower parts count, smaller case, lower manufacturing cost).  The CoCo 2 shipped in 16 KB and 64 KB RAM configurations. 
  • Motorola 6809E CPU
  • 64K RAM 
  • Cartridge slot
  • Plugs into any TV
  • Model number 26-3127 
  • SN; 0003289
The COCO 3
Introduced in 1986, the COCO 3 incorporated a number of very significant improvements.  The original clock speed of 0.895 MHz was doubled to 1.7 MHz (with the CPU appropriately changed to a 68B09E), and a new video/memory-management chip. 
  • Motorola 68B09E CPU
  • 128K RAM
  • Extended color basic v2.0
  • RGB out and Audio/Video out and RF out
  • Cassette I/O and Serial I/O
  • Cartridge slot
  • Joysticks left and right 
  • Model; 26-3334
  • SN;109931
Click here for a brief history of Radio Shack Computers.

pcbiography.net