Patent ID: 6940974

Claim:
A system for generating number tones for dialing a telephone device comprising a microphone, comprising: a housing defining a sound opening; a first data entry device supported by the housing, where the first data entry device is associated with a first sequence of stored digits; a first memory device for storing the first sequence of stored digits; a second memory device for storing frequency data associated with number tones; an output signal generator for generating, upon activation of the first data entry device, an output signal based on the first sequence of stored digits and the frequency data; a transducer mounted within the housing adjacent to the sound opening for converting the output signal into an audible signal; and a printed circuit board mounted within the housing adjacent to the transducer for supporting the output signal generator, where at least one opening is formed in the printed circuit board; whereby the housing is adapted to be attached to the telephone device with the sound opening adjacent to the microphone; and the at least one opening in the printed circuit board is sized and dimensioned to reduce back pressure on the transducer.