In one embodiment, a block code decoder is provided. The handgrip includes an internal sleeve positioned over the shaft of the colonoscope so that it can be released and repositioned by depressing a release button. This capacitive coupling improves the response time of the resistive divider, so that a scaled test voltage read from the tap point varies more rapidly than the elevated output voltage of the voltage multiplier circuit. For example, a thermoelectric cooler can be used to heat or cool the laser diode as necessary to thereby adjust the wavelength of the emitted light. By determining the sequence of the segment of the heterologous nucleic acid of a package within a complex, one can identify the target protein since the segment encodes for an epitope that is shared by the expressed and target proteins. In order to provide for improved balance control and visibility, the filter system is positioned in the rear of the helmet.