Systems and methods of retraining a receiver provide for determining a minimum transition density for a derived clock data link to the receiver. A dual-positioned detent mechanism alternately holds the plunger in a labial, open position exposing the notch and a lingual locked position wherein the section of arch wire captured by the notch is securely held in a diametral slot cut into the bracket. The variable resistor includes a plurality of resistor segments in the variable resistor and, when a plurality of resistance candidates for the variable resistor is arranged in order of size, the resistance candidates form a geometric series. Certain embodiments of the invention may be retrofitted to coupling members of the prior art. Then, the image display member and the light-transmissive cover member are laminated to each other via the light-transmissive cured resin layer to obtain an image display apparatus.