US 5,495,527 A · Telephone privacy device

Abstract

A telephone privacy device includes first and second connectors that are mateable with a telephone handset and a telephone base, respectively. The handset includes a microphone, and the device includes a variable amplifier that allows the user to amplify the microphone signal to a desired level prior to sending it on to the base. A signal strength display allows the user to monitor the amplitude of the amplified microphone signal. A side tone suppression circuit generates a side tone suppression signal in response to the amplified microphone signal. This side tone suppression signal is used to reduce excessive side tone from the telephone base. An adjustable gain amplifier amplifies the speaker signal supplied by the base for the handset speaker.

Claims22

Dependent claims

A telephone privacy device for a telephone comprising a base and a handset, said device comprising:

a first connector configured to receive a microphone signal from a microphone included in the handset;
a variable amplifier coupled to the first connector to receive the microphone signal and to generate an amplified microphone signal, said variable amplifier comprising a user adjustable volume control element effective to adjust amplification of the variable amplifier to an adjustable degree;
a signal strength display responsive to the amplified microphone signal to provide a visual indication of signal strength of the amplified microphone signal to a user;
and
a second connector coupled to the variable amplifier to transmit the amplified microphone signal to the base.

2 more elements

A telephone privacy device for a telephone comprising a base and a handset, said device comprising:

a first connector configured to receive a voice signal from a microphone included in the handset and to supply an amplified speaker signal to a speaker included in the handset;
a variable amplifier coupled to the first connector to receive the microphone signal and to generate an amplified microphone signal, said variable amplifier comprising a user adjustable volume control element effective to adjust amplification of the variable amplifier to an adjustable degree;
a second connector coupled to the variable amplifier to transmit the amplified microphone signal to the telephone base, said second connector further configured to receive a speaker signal from the telephone base;
a second amplifier responsive to the speaker signal from the second connector and operative to supply the amplified speaker signal to the first connector;
a side tone suppression circuit having an input responsive to the amplified microphone signal and an output coupled to the second amplifier to supply a side tone suppression signal to the second amplifier that varies in amplitude in response to the amplified microphone signal.

2 more elements

Dependencies are inferred from the claim text.

Telephone privacy device

Life of this patent

Telephone privacy device

Life of this patent

Abstract

Claims22