lights for standing pins, triangular corner lights that indicated the first or second ball to be rolled, and separate lights to indicate a foul, or a strike. The "arrows" were for the purpose of advising an inexperienced bowler to assist in spare conversion, by indicating where a second ball delivery should hit the remaining pins for a successful conversion, and were triggered by appropriate combinations of standing pins that helped the machine select which one of the eleven arrows to illuminate. Rear view of an AMF Magic Triangle screen and the patent document for it There have been specific upgrades and improvements made to the machines produced after the 82-30, with after-market solid-state/microprocessor-operated controllers available for the 82-30 itself. The 82-70 is the general standard in most AMF-equipped modern bowling centers today. It features a microprocessor-operated chassis that is upgraded to short cycle the machine for strikes, gutter balls, or 7–10 pick-offs. It features solid state motors. The 82-90 and the 82-90XLI are further upgrades, basically using the 82-70's mechanics, which replaced the older, completely electro-mechanical controls with machine status indicator lights, much more sophisticated "pin storage" design, single control centers that handle two machines, and perhaps the most important upgrade is the self shutdown control, which shuts the machine down to prevent damage from continuing to operate with a fault. The 82-90 models feature a deck that is thinner than the 82-70. QubicaAMF Worldwide has also introduced many different scoring systems that are compatible with all pinsetters and pinspotters. Brunswick A series pinsetters The Brunswick Model A, dating from 1956, as well as the developed A2 (1962) and the JetBack (1965) versions of it, work as follows. When an A series pinsetter starts the reset process, balls and pins are pushed off the end of the lane by the rake or sweep onto a shaker board in place of the AMF-variety carpet belt. This "shaker board" transfers the ball and pins to the back of the pit, behind the lane's pindeck. Two rotating wheels, at the backside of the unit, are situated with their common axis along the bowling lane. The ball-lift wheel is the front most wheel and has a continuous smooth surface with cork strips adhered to grip and push the ball onto the lift rods. Pins fall rearwards through the unit into the pin wheel, which capture the pins and sends them up to the pin