Micropolis 1200-Series


1200-Series of rigid disk systems

Model Number 1201-1 1202-1 1203-1
Capacity (MFM) 7MB 20MB 35MB
Platters 1 2 3
Heads / Data Surfaces 1 3 5


The Micropolis 1200 series of hard disk drives is a lineup of three models of full height 8-inch storage devices. Designed in 1979 and introduced in 1982, they represent a first step in Micropolis' early storage solutions. The actual platter containment is of lower height, making space for a controller board sandwiched on top while fitting the 8 inch Shugart mounting slot. Note that the drives in this series all have a proprietary ANSI inferface.

As Micropolis Corporation's first step into hard-disk technology, these drives share many traits with their floppy disk predecessors. These early drives have no fixed formatting. Instead, the magnetic surface can be utilized to write any format of data inside tracks and even track density is variable. The controller board in use determines the format written. Common choices are MFM and GCR encoding schemes. Please refer to the series' specifications below for differences in capacity and performance with MFM and GCR encoding. The device's mechanical drive mechanism is accurate enough to satisfy positioning needs of MFM, GCR and RLL encoded information on the platter.

MFM is short for "Modified frequency modulation". RLL means "Run-length limited". GCR abbreviates "Group coded recording".

These hard disk drives were sometimes marketed as Micropolis MicroDisk™ as they were - despite their large outer envelope from todays perspective - designed to be used with "mini" and "microcomputers" of the time. Micropolis used the "MicroDisk™" model name on a number of products. For the early 1200 series 8-inch hard-disk drives described here but, mainly, for the simple external storage subsystems 670/1030 which carried the name MicroDisk. When the Raidion series of stackable SCSI subsystems was introduced, an early production run was also labeled MicroDisk.

Video of Model 1203-1