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AssigneeNEC Corporation
InventorYukio Murata
Estimating the term…
A hands-free telephone for use on a vehicle includes a handset incorporating a radio section therein and a hands-free adapter incorporating a hands-free telephone unit therein. To prevent howling, the telephone includes two variable attenuators, or variolossers, each for changing the level of respective ones of a receive and a transmit signal to be applied to a speaker of the hands-free telephone unit and the radio section, respectively, so as to maintain the two levels in a predetermined relation. The telephone also includes in the radio section a variable resistor which may adjust the volume of voice signal to be delivered through an earpiece within the radio section which adjusts the volume of voice signal to be delivered through the speaker. The level-adjusted voice signal to be delivered through the speaker is controlled in level by a third variable attenuator simultaneously with the above-mentioned variable attenuators.
A hands-free telephone comprising:
A telephone as claimed 1, wherein said third and fourth attenuating sections have the same attenuation characteristic.
An apparatus having a handset and a hands-free unit, said handset comprising:
An apparatus as claimed 4, further comprising:
A method of controlling the output level of a speaker in a hands-free telephone, comprising the following steps of:
A hands-free telephone comprising:
A hands-free telephone comprising:
In a combination of a hands-free telephone unit and a radio section,
Dependencies are inferred from the claim text.