Zenith 248 SX
The Zenith 248 was a desktop computer with two 5ΒΌ inch floppy drives and no hard drive, released in 1986. It came with Windows operating system on floppies. It was manufactured by Zenith Data Systems. This model was delivered to all incoming cadets at West Point, NY in 1986 for the class of 1990 along with the other service academies.
The 248 continued to be produced thru 1990, it contained a passive backplane containing only a small number of diodes. Daughter cards include a CPU board and an I/O board for parallel port, serial port and disk IO ports. The systems commonly were purchased with Seagate 20MB MFM or Hitachi 40MB MFM hard disk (the Hitachi design included an external mounted CAM, one of very hard disks for microcomputer ever design with external moving parts) and contained 1 MB of RAM. Upgrades were available by adding additional daughter cards for an addition 1MB of RAM. Early programs includes Enable AO, Word Perfect and Harvard Graphics. 1MB memory upgrades were required to support advanced printing, such as using Sideways to print spreadsheets in landscape.
Common in the U.S. Navy 1989-1990 in part due to a design that allowed for easy repairs by stocking FRUs, field replaceable units of CPU and IO boards. The Navy also used a portable depot level repair machines called a VU-DATA. Using a LCD, the VU DATA instructed the operator to test high and low pins throughout a CPU or IO board then prompted to replace ICs to repair daughter boards. Spinrite was commonly used at this time to repair hard disks. The Seagate hard disks also had field replaceable circuit boards making the Zenith 248 a supportable system when deployed at sea.
The U.S. Air force also used the 248s with the 20 and 40mb hard drive and were commonly used in orderly rooms and tech admin offices. The unit was issued with a 12 inch black and white monitor and had double 5 1/4 inch floppy drives. Most of them could be loaded with a database program, a word processing program and a spread sheet program. Branch offices in the squadrons loaded the Data base 3 and Word Star or word perfect programs with formatted discs and copied programs. Site licenses were used sometimes at base level so that the programs could be mass produced and used when data got corrupted in the program discs. At Spangdahlem AFB,Germany in 1989 it there wasn't a computer specialist field, only data entry personnel. The wing used aircraft maintenance personnel with experience in computers that volunteered to assist with duplicating software, troubleshooting hardware and doing repairs within the wing.