In an excited state Wozniak got on the phone and called his best mate and fellow electronics geek, Steve Jobs, and together they set off to find a library that still had the journal on its shelves. They got lucky and immediately set about producing a device that utilised a frequency counter to calibrate the desired tones. Unfortunately for them, their first attempt didn't quite work and was unable to fool the phone company. Undeterred, Wozniak agreed to continue on the project by developing a digital version of the device by using diodes and transistors.
Once it had been completed, the two attempted to call Wozniak's uncle in Los Angeles, but by mistake got a wrong number. It didn't matter - it worked perfectly.
As a result, the two came to realise that the device, which they dubbed a Blue Box could be built in huge numbers and sold. The units would cost them $40 to manufacture, so Jobs decided to price them at $150. They demonstrated them at college and swiftly sold around 100 units. But their endeavour came to a swift end when trying to sell it at a pizza parlour, they were quite literally mugged at gunpoint.
Steve Jobs was to later recount the episode as being the spark that launched Apple. The two friends had an affinity when it came to solving technical problems and together formed an invincible and incredibly focused team. When quizzed on the subject by Walter Isaacson, Jobs later confessed: "If it hadn't been for the Blue Boxes there wouldn't have been an Apple."
Alex Pearl is author of Sleeping with the Blackbirds