JPH02190066A - Sidetone prevention type telephone set - Google Patents

Abstract

PURPOSE:To prevent sidetone completely and to device the subject telephone set to easily listen to an opposite voice even at a location where surrounding noise is large by providing a switch interrupting a voice output from a transmitter section on the telephone set connecting to a 2-wire telephone circuit. CONSTITUTION:The handset 1 of a telephone set connecting to a 2-wire telephone circuit is provided with a switch 2 connecting to the output of a transmitter section 3 in addition to the transmitter section 3 and a receiver section 4. When a voice from an opposite party is hard of hearing because noise is remarkably large, the switch 2 interrupts the output of the transmitter section to prevent sidetone from entering the receiver section 4. Thus, side tone is completely prevented to allow to easily listen to the opposite voice.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a telephone set connected to a two-wire telephone line.

[Prior Art] Conventionally, this type of telephone has used a sidetone balancing method to prevent sidetone, which takes into account the resistance value of the transmitter, the psychological unnaturalness of talking, etc. A booster circuit is used.

[Problems to be Solved by the Invention] The conventional telephone described above has a two-stage sidetone balancing circuit network, but the reduction in side volume is limited to a certain limit. If the device is used in a place with an extremely large volume, it may be difficult to hear the other party's voice.

[Means for Solving the Problems] The sound-protecting telephone of the present invention has a switch that cuts off the audio output of the transmitter.

[Function] Therefore, whenever it is difficult to hear the other party's voice due to sidetones, the switch can be used to cut off the voice output to prevent sidetones from entering the receiver, thereby making it easier to talk.

[Example] Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is an external view of an embodiment of a sound type telephone of the present invention;
FIG. 2 is a circuit diagram of the main part.

The handset 1 includes a transmitting section 3, a receiving section 4, and a switch 2 connected to the output of the transmitting section 3, as shown in FIG.

Therefore, when the noise is extremely loud and it is difficult to hear the voice of the other party, by shutting off the output of the transmitting unit with the switch 2, side sounds can be completely prevented and the voice of the other party can be easily heard.

[Effects of the Invention] As explained above, the present invention has a switch that cuts off the audio output of the transmitting unit, so that side noise can be completely prevented. This has the effect of making it easier to hear the voice.

[Brief explanation of the drawing]

FIG. 1 is an external view of an embodiment of a sound type telephone of the present invention;
FIG. 2 is a circuit diagram of the main part. DESCRIPTION OF SYMBOLS 1... Handset and receiver, 2... Switch, 3... Transmitter, 4... Receiver. 1 handset

Claims (1)

[Claims] 1. A telephone connected to a one- or two-wire telephone line, characterized in that it has a switch for cutting off audio output from a transmitter.