4)    Are all electronic machines based on the same technology?

Important differences distinguish the technologies used in various electronic machines. There are four types of technologies. The first consists of electronics for direct torque control of a motor so that the motor cannot pull more than the desired tension. Silent Partner holds a patent for this technology (US Patent #6,162,139) and offers it exclusively on the e.Stringer, the e.Stringer CL and the e.Stringer FL, as well as in retrofit tensioners for other brands of machines. The second type of electronic technology consists of a motor control linked mechanically to a pre-loaded spring. Tension adjustment is effected by turning a knob that compresses the spring to the desired tension so that a limit switch is tripped and the motor is stopped when the tension is reached. This type of control, which is identified by a tension control knob located to the right of the machine (see picture), does not provide constant pull because tension has to drop by more than 15 lbs. for the limit switch to turn the motor on again, and this does not normally happen during stringing. The third type of electronic technology is the most sophisticated and relies on a potentiometer monitored by a microprocessor. This technology offers the potential for many keypad controlled features. This is the technology used in the e.Stringer DG. The most sophisticated electronic machines use a load cell and microprocessor. This is the technology used in the Silent Partner Aria and the new Silent Partner Opus.