A method and apparatus for securely registering an association between a computer terminal and a selected one of a plurality of communications terminals in a computer telephony system. The \u201ctune\u201d of the person’s name is played on, e. The stabilizing wheel has a function for guiding the bogie along to the monorail and a function for presenting a falling of the bogie. The axial electric field is substantially linear across the central section of the i\xf8n trap, but the electric field is distorted across both ends of the ion trap. The second elongate structure is brought into a predetermined guiding relationship with the guiding portion of the guiding frame.