Sphere Corporation's "Pleaser" PC from the mid-1970s

This advertisement appears on the back cover of the June 1976 issue of Interface, a home computerist magazine of the Southern California Computer Society. (I've seen the magazine elsewhere referred to as SCCS Interface Age.)

Here are some of the personal computer's specs, as described in the advertising copy:

• "We have a Central Processing Unit (CPU) that contains the most advanced technology available today. That means to you that the CPU will do what a CPU ought to do. It's reliable."
• "We have a Serial Interace Module (SIM) that is a very powerful idea in the computer world today. Let me explain. You can have an inexpensive audio cassette player/recorder as a mass-memory storage device. ... For just pennies you can store vast amounts of Data on an ordinary audio cassette."
• "We have a Program Development System (PDS) that is an aid to programming. What an idea! It remembers its job even when the computer is off."
• "As if that weren't enough ... we have a newly added feature THE 4K ROM BD. A board containing up to 4000 bytes of Read Only Memory."

This "powerful" machine seems to be a version of the Sphere 1, which, according to Wikipedia, "featured a Motorola 6800 CPU, onboard ROM, a full-sized CRT monitor, 4 KB of RAM, and a keyboard with a numeric keypad." Also according to Wikipedia, it sold about 1,300 units between 1975 and 1977 before the computer and the Utah-based company faded away. 

The Sphere 1 cost $860 as a kit or $1,400 assembled; in today's dollars, that's $3,971 and $6,465. 

There were also expensive upgrades available. You could add a modem, 20K of memory, a floppy disk drive and a line printer. The top-of-the-line Sphere 4, with all of those enhancements, cost $7,995 assembled, which is the equivalent of $36,922 today. 

I agree with Joan, who says, "That's a lot of dollars." Home computing was crazy expensive in the 1970s.

Sphere 1 was the creation of Michael Donald Wise (1949-2002), who, as history-computer.com notes, did leave a legacy within the industry:

"Michael Wise was an inventor and creative genius, not a businessman. His company began advertising before the product was fully debugged in order to finance its growth. Enormous, unexpected demand overwhelmed the company, which was literally killed by success. ... Competitors quickly filled the void. Nonetheless, the Sphere had made its mark on the history of the personal computer, and contributed to both the specs and design of future generations of hardware. Sphere 1 inspired many copycats."

Another part of Wise's legacy is that he essentially came up with the idea of Control-Alt-Delete. As bugbookmuseum.blogspot.com noted in 2013:

"One feature that Michael designed into the [Sphere 1] computer was the ability to reboot the computer by holding down 2 keys at the same time. This was the first for this kind of hard reboot. Now were have the (Ctrl-Alt- Delete) function  & it is same idea of gaining control of your computer."

The version of Control-Alt-Delete that we're more specifically familiar with today is credited to engineer David Bradley.