Editing Group coded recording (section)

=== Durango ===<!-- used in redirects -->
The [[Durango Systems]] [[Durango F-85|F-85]] (introduced in September 1978<ref name="Schultz_1978_Durango" /><ref name="Hendrie_2003_Comstock" />) used single-sided 5¼-inch 100&nbsp;tpi diskette drives providing 480&nbsp;KB utilizing a proprietary high-density 4/5 group coded encoding. The machine was using a [[Western Digital FD1781]] floppy disk controller, designed by a former Sperry ISS engineer,<ref name="Guzis_2015_Multi" /> with 77-track Micropolis drives.<ref name="Guzis_2009_Micropolis" /> In later models such as the [[Durango 800]]<ref name="Durango_800" /> series this was expanded to a double-sided option for 960&nbsp;KB (946&nbsp;KB formatted<ref name="Durango_800" /><ref group="nb" name="NB_On-line_capacity" />) per diskette.<ref name="Hendrie_2003_Comstock" /><ref name="Guzis_2006_F85" /><ref name="Guzis_2009_Micropolis" /><ref name="Micropolis_1978" />