Radio Shack always knew how to market at Christmas (see links below). In the 1970s and '80s, the firm produced more Christmas-themed computer ads than any other company in the US.
Here's one of the earliest ones from 1978. It features the company's first personal computer, the TRS-80, which first launched in 1977. After other models of TRS-80 computer came out, Radio Shack began referring to it as the "Model I."
But that wasn't the only name this pioneering computer earned. The original TRS-80 was the first personal computer my dad ever bought, not long after it launched. He found it frustrating, sold it, and later bought an Atari 800 for my brother — then hand-built an Apple II clone for himself.
Thereafter, my dad always referred to that first TRS-80 as his "Trash-80," which was a common nickname for the computer. It could double as a derogatory play on words or a beloved pet name, depending on whom you asked. For my dad, I suspect it was more of the former than the latter.
Discussion Topic: What's the worst present you've ever received for Christmas?