Anyone can use GPS today, and the history behind that technology is truly fascinating, but on more than one occasion we have explored the possibility of using non-satellite navigation systems in our cars. Some readers probably remember the Etak Navigator that debuted in the mid-80s; however, today we come across a very old episode of the BBC's Tomorrow’s World program, which presented the existence of a prototype navigator based on audio cassettes with pre-recorded instructions.
The year was 1971. Anyone who had to go to a specific address in their car and got lost along the way generally had two options: use a traditional map or ask a local resident. It sounds like prehistory… but that's how things worked.
The idea of a personal, vehicle-integrated navigator was very attractive, and some brilliant minds of that era tried to do everything possible to overcome existing technical limitations. One of the first prototypes was presented in an episode of Tomorrow’s World (which was already in its sixth year, with Michael Rodd as presenter), and its appearance on the show included a demonstration.
Before GPS: Cassette Navigation in 1971
As you can see in the video, the navigation commands were verbal, not visual. In essence, the entire navigator depended on compact cassettes and the car's radio-cassette system.
Each command was separated by a “blip” with an encoded distance value. That value was recorded by the control unit installed under the dashboard, which managed the operation of the player. At the same time, the unit had to be connected to the car's odometer to determine (to a certain extent) the distance traveled and give way to the next instruction.
That brings us to one of the most serious problems of the entire system. Leaving aside the detail of “a cassette per route,” the accuracy of the odometer depends on several factors, starting with the size (programmed with a special circuit) and the tire pressure.
On the other hand, a simple wrong turn could completely ruin the rest of the instructions, just like a closed street (whether due to an accident or construction)... and let's not forget that those players had the unpleasant habit of eating tapes.
