Disclosed herein is a method and apparatus for moir\xe9-free color halftone printing with up to four color image separations. The stimulation device generates a ventricular stimulation pulse to trigger an evoked response, in order to produce a ventricular far-field signal that follows a successfully captured ventricular stimulation pulse. The present invention also concerns materials and methods for removing aurintricarboxylic acid from a sample. Maintaining the pH of the washwater solution reduces the corrosion rate of the glass fiber forming equipment that is typically associated with acidic binders. The antenna coupling element is inductively coupled with the surface antenna pattern for transceiving the signals to the electronic device.