This was all to change in 1969, when the Electronics Industries Association of Japan, or EIAJ, called up a meeting with all the companies making industrial-market VTRs to have them all sit down and design and decide on an industry-standard format, which would ensure all recordings made on one manufacturer’s VTR could play back on another from a different manufacturer. Hence, the EIAJ format was born. It used 7″-diameter open-reels of 1/2″-wide videotape, and originally recorded black and white video (later VTRs using the EIAJ format in the early 1970s would offer color video as well).
The EIAJ format made non-professional industrial video standardized, and as a result, more affordable and attractive to purchase. Many schools, businesses, and some of the first cable access TV channels debuting in the early 70’s made heavy use of EIAJ. It would pave the way for the VTR industry to invade the home just a few short years later.
There are two very good and very informative web sites featuring these post-2″ quad and pre-VHS & Beta machines in all their retro glory, Labguy’s World (where I got the image above), and Quadruplex Park, which focuses more on professional broadcast machines (such as 2″ quad), but also focuses on the VTRs in mention here.