Whether you are a general consumer, professional electronics user or a datacenter support technician/engineer, the appearance and handling of connectors and cables has been and can still be a sometimes bewildering or even gnarly experience. There are many factors to consider. Let’s take a backward, current and near future look at the evolution of I/O plug connector and cable industrial design.
Back in the 1970s, connector plugs were macro-size as they filled the palm of a medium to large hand and used much of all finger lengths to grip. People with smaller hands and fingers sometimes needed to use both of their hands to connect or disconnect an I/O interface copper cable assembly. It seemed most plugs and cable were too big for the average person to deal with especially in manufacturing.
Large, grey, thick metal backshells with 6-60 size or larger metal jackscrew fasteners were typical. The cable and wire conductors were also very large diameter, usually between 18-22 AWG. This caused the cable assembly to be very heavy and often awkward to align and and it was difficult to push the plug into its mating receptacle connector. Plug shapes were very rectangular and block-like, with giant ribbed gripping features. It seemed there also were 25 shades of grey over-molded plugs, with usually smooth matte finishes and cable outer jackets. Even some raw cable had linear ribbed jackets. Test, measurement and telephony equipment set the industrial design norm.
In the 1980s, connector plug sizes were usually called miniature, sometimes subminiature and generally were about one-third less in overall size. This new size range made connecting easier. Metal back-shells seemed to disappear and over-molded plugs with internal thin metal shields were most common. Size 4-40 molded thumbscrews were much easier to use and took less time to fasten. Typical wire gauge size shrunk to mostly 24 AWG, but circuit count was usually higher so cable diameters were still large or huge, which still caused awkward cable handling and routing. It seemed that the 25 shades of beige over-molded plugs evolved through the decade. Everything seemed to appear the same and people got bored with this. Desktop and business office equipment set the I.D. norm.
During the 1990s, connector plug sizes shrunk again and were mostly called subminiature with some micro-miniature. This was again about 30% smaller in average size. Average wire size dropped to 26-28 AWG. Over-molded plugs saw increased competition from plastic back-shells with sprayed metal inside for shielding. Finally, average cable diameters began to shrink through this decade along with average component and assembly weights. Overall design was much more ergonomic and accounted for better air flow in racks of active equipment. Fasteners were more often latches or push-pull types enabling more efficient build times.
Plug housings, backshells and over-moldings and cable jackets were almost all black in color. Black became industrial design beautiful and was viewed as a cleaner look though grit and film still formed on these connectors and cables from the general environment usages. However, with everything being so black and dark in the racks, it was hard to see and locate the right cable plug to disconnect or where to connect it.