I've never owned a Visual 1050 Personal Computer System (seen here), but I have an old Visual brand terminal that uses the same (or a very similar) keyboard. That's the first thing that comes to mind when I see this, because it's a distinctively wide, flat keyboard.
The 1050 sported a Z80 CPU and ran the CP/M operating system, the grandfather of MS-DOS. Curiously, even though CP/M was a popular platform for business computers in the late 1970s and early 1980s, I only have a a handful of pure CP/M-based machines in my collection. (My favorite such machine is probably the Kaypro II.)
In regard to the chart in the advertisement above, it's interesting to note that it was pretty easy to undercut IBM, price-wise, not long after the IBM PC came out. Fast advances in IC design allowed computer makers to inexpensively cram more functions (think serial, parallel, game ports, disk controller, graphics card, etc.) directly onto motherboards instead of offloading them onto separate plug-in cards. While the 1050 was not an IBM PC clone, true PC clone makers took advantage of this effect to hollow out the inside of IBM's hold on the PC market from the bottom up.
Discussion Topic of the Week: Do you have a favorite machine that runs CP/M?