Atom industries invented the Hall Effect Trigger for small engines back in 1962 and Husqvarna , Stihl & Victa inroduced it into some of their engines the following year.
No other engine maker would pay the 20¢ royalty per unit nor buy developement rights but just waited till the patients expired ,
Back then Australian patients ran for different times in different places ranging from 15 years locally to 30 years in third world countries.
So B & S did not intorduce their reverse engineered copy of the atom called the magnetron ignition till 1977
Atom continued to make their Briggs & Stratton ( brown ) points replacement kit till 2000 .
All of the others were dropped in 1995
Actually it was 1982 with the introduction of the magnetron. Got that straight from the The legacy of Briggs and Stratton book that I have. Which gives the full history of the company
So USA recognition of Aust patients must have been 20 years.
I would have sworn it was only 15 , the same as it is now under the current USA/Aust "free trade" deal.
So we must have given up a little more that I thought.
Depending on time frame it could of been officially introduced on the 1983 engine year engines, Which of been fall winter 1982 for the update school. I was actually thinking it was 1983 myself until I grabbed the book off the shelf.
