9 Computer, mother board, computer disk drive, compact disk drive, computer keyboard, portable hard disk drive, magnetic coded card readers, computer software recorded on CD-ROM for electronic voice messaging telephone system; safety goggles, audio speakers, sound amplifiers, microphone, sound equalizer; loudspeaker cabinet, stereo headphone receivers; power supplies, power stabilizers, uninterruped power supplies; telephones; speaker-phones wireless phone, cellular phone; wireless pagers; audio signal receivers; audio signal transformer