JPS6010954A - Telephone set - Google Patents

Abstract

PURPOSE:To decrease the effect of noise mixed from a curl cord during calling by providing an amplifier in a handset main body in a telephone set using a capacitor electric microphone as a transmitter microphone. CONSTITUTION:The capacitor electric microphone is used as the transmitter microphone 7, and an amplifier with high input impedance and a low output impedance is used as an amplifier 4 and they are provided in the handset main body 6. Further, the voice of the user is inputted to the transmitter microphone 7 with respect to the transmission, and after the voice is amplified by an amplifier 3, the voice is transmitted to a telephone set main body 1 via the curl cord 9. Thus, the signal level passing through the curl cord 9 is comparatively large and the noise from the curl cord is reduced effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a telephone set that uses a condenser electric link microphone as a transmitting microphone.

Conventional Structure and Problems Generally used telephones are all structured as shown in FIG. In FIG. 1, l is the main body of the telephone, a telephone transformer 2 connected to the exchange, and a hybrid circuit 3 forming a transmission/reception communication path between the exchange and the telephone.
, an amplifier 4.5 for transmitting a call, and an amplifier 4.5 for receiving a call. 6 is connected to the phone body I via curl cord 9.1o
The main body of the handset is K-connected, and includes a microponse 7 for sending and a speaker 8 for receiving.

Regarding reception, the voice signal from the exchange is applied to the reception speaker 8 via the communication transformer 2, the hybrid circuit 3, the amplifier 5, and the curl cord 1o in this order. For transmission, the voice is input to the microphone 7 for transmission, the curl cord 9, the amplifier 4, and the hybrid circuit 3.
, and is output to the exchange via the telephone transformer 2. Normally, carbon micropons are often used as the transmitting microphone 7, but recently condenser electric microphones have become a hot topic, and it is said that using them will improve sound quality, make them smaller, and lower costs. ing.

However, as in the past, the amplifier circuit 4 is not connected to the telephone main body 1.
For those installed on the side, the condenser electric microphone itself has a high output impedance.
1. Therefore, if a telephone user touches a curl cord 9.10 etc. by hand during a call, this will induce noise, which will mix into the call signal and significantly reduce the quality of the call itself. There was a problem.

Purpose of the Invention The present invention eliminates the problems of the above-mentioned conventional example,
To provide an excellent telephone set in which the influence of noise mixed into a communication path is extremely small even if the curl cord is touched by hand during transmission.

Structure of the Invention In order to achieve the above-mentioned object, the present invention provides an amplifier inside the handset body, and uses this amplifier to amplify the audio signal etc. from the transmitting microphone, thereby reducing the influence of noise mixed in from the curl cord etc. In addition to improving the signal-to-noise ratio, the output impedance is made low by the amplifier, and the ingress of noise into the communication path is significantly reduced.

DESCRIPTION OF EMBODIMENTS The configuration of an embodiment of a telephone according to the present invention will be described below with reference to the drawings.

FIG. 2 is a schematic diagram of an embodiment of the telephone according to the present invention, and the same reference numerals as in FIG. 1 indicate the same components as in FIG. In this embodiment, a condenser electric microphone is used as the transmitting microphone 7, and an amplifier 4 with high input impedance and low output impedance is used, and these are installed in the handset body 6. . Further, numeral 11 is a power supply coat for supplying power to the handset main body 6 side. In the embodiment shown in FIG. 2, the reception of calls is the same as the conventional one shown in FIG. It is transmitted to the telephone main body 1 side via the back curl cord 9. Therefore, the signal level passing through the curl cord 9 is relatively high, and the output impedance of the amplifier 4 when viewed from the curl cord 9 side by φ is also low, resulting in a significant improvement in the S/N ratio. In fact, even if the curl cord 9 is grabbed by hand, it is possible to obtain the effect that almost no noise is mixed into the communication path.

Effects of the Invention As is clear from the above-mentioned embodiments, the present invention is constructed so that the signal from the telephone microphone is amplified by an amplifier in the handset body and transmitted to the telephone body. The signal output to the main unit has a relatively high output level and is transmitted with low output impedance, which greatly improves the S/N ratio and eliminates noise that may enter the communication path even if you grab a curled cord by hand. is relatively small, which is extremely advantageous in practice.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional telephone, and FIG. 2 is a schematic diagram of an embodiment of a telephone according to the present invention. ■...Telephone body, 2...Telephone transformer, 3...No...
Ibrid circuit, 4.5...Amplifier, 6. Handset/receiver body, 7..Microphone for sending, speaker for meter/receiving, 9.10, 11...Curl cord.

Claims (1)

[Claims] This telephone set uses a condenser electric link microphone as a transmitting microphone, and houses this microphone and an amplifier with high input impedance and low output impedance for amplifying the signal from this microphone in the handset body.