JPH0198351A - Telephone set circuit - Google Patents

Abstract

PURPOSE:To change over a transmission/reception level automatically at extension and external line communication by providing a means detecting an external line outgoing mode at the external line communication so as to extract a handset pad. CONSTITUTION:In case of external line communication, after a hook switch 9 is hooked off and an external line dialing key 11 is depressed, then a control circuit 10 throws the contact of a transmission changeover switch circuit 3 and a reception changeover switch circuit 6. Thus, The input/output of a transmission pad 4 and a reception pad 5 are short-circuited to increase the transmission/reception level. On the other hand, in case of extension communication, since the external line dial key 11 is not depressed, the control circuit 10 turns off contacts of the circuits 3, 6. Since the transmitter 8 via a transmission pad 4 and the receiver 8 via a reception pad 6 are connected to a channel, the transmission/reception level is suppressed properly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a telephone set, and more particularly to a telephone circuit connected to a private branch exchange, which reduces the difference in transmission and reception levels between internal calls and external calls.

(Prior Art) Conventionally, when this type of telephone is connected to a private branch exchange, the transmitting/receiving level switch is set so that the transmitting/receiving level is within a range that is approximately compatible with the extension of the private branch exchange to which it is connected. Fixed.

(Problems to be Solved by the Invention) When the above-mentioned conventional telephones are first installed, the adjustment changeover switch is manually changed and set to a fixed level so that the transmission/reception level matches the extension. Since the line loss is small in calls between internal lines and large in calls between external lines, there is a drawback that the transmission and reception level differs greatly between internal calls and external calls. Therefore, if you initially set the bell to the optimal level for internal calls, it may be difficult for both parties to hear external calls, and if you set the bell to the optimal level for external calls, internal calls may be heard too loudly. be.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a telephone circuit that solves these problems and automatically reduces the difference in transmission and reception levels between an internal call and an outside call.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the telephone circuit of the present invention has the following features: Short-circuit and open the input and output of the transmitting pad 4, which is inserted between the handset 8 and the telephone circuit 2, which is inserted between the receiver 8 and the telephone circuit 2, and which adjusts the receiving level, and the transmitting pad 40. A switch circuit 3 for switching between calls and a switch circuit 6 for switching between calls that short-circuits and opens the input and output of the receiving pad 5, and a signal that is sent only when the outside line call key 11 is pressed by keyboard operation. It has a control circuit 10 that short-circuits the call switching switch circuit 3 and the receiver switching switch circuit 6.

(Example) Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment according to the present invention.

As shown in FIG. 1, a communication circuit 2 is connected to a line via a rectifier stack 1. As shown in FIG. The transmitter 7 is the transmitter pad 4
The telephone receiver 8 is connected to the communication circuit 2 via the receiving pad 5. An on/off contact of the transmitting switch circuit 30 is connected in parallel between the input and output of the transmitting pad 40, and an on/off contact of the receiving switch circuit 6 is connected in parallel between the input and output of the receiving pad 5. There is. A hook switch 9, an outgoing call key contact 11 of a private branch exchange (not shown), a transmitting switch circuit 3, and a receiving switch circuit 6 are connected to the control circuit IO.

Next, the operation will be explained.

When making an outside line call, after turning off the hook switch 9 and pressing the outside line call key 11, the control circuit 1
0 turns on the contacts of the transmitting switch circuit 3 and the receiving switch circuit 6 to short-circuit the input and output of the transmitting pad 4 and the receiving pad 5 to increase the transmitting/receiving level. When making an internal call, even if the hook switch 9 is off-hook, the external call key 1 is pressed.
1 is not pressed, or even if it is pressed, the control circuit 10 turns off the contacts of the transmitter switch circuit 3 and the receiver switch circuit 6, so that the transmitter switch is disabled. 7 is the transmitting pad 4
8 and the receiver 8 is connected to the telephone circuit via the receiving pad 6, so that the level of transmission and reception is appropriately suppressed.

Therefore, it is possible to automatically reduce the difference in the transmission/reception level between an outside call and an internal call.

(Effects of the Invention) As explained above, the present invention is used by connecting to a private branch exchange, detects the outside line coloring mode during an outside line call, and automatically switches the transmission/reception level by removing the transmission/reception pad. This has the effect of reducing the difference in the transmission and reception level between an external call and an internal call.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention. 1... Rectifier stack 2...Telephone circuit 3...Switch circuit for switching the transmitting voice 4...Pad for calling 5...Pad for receiving calls 6...Switch circuit for receiving calls 7...Telephone 8...Telephone receiver 9...Hook switch 10...control circuit 11...External call key Patent applicant: NEC Corporation Representative patent attorney Hisashi Inoro

Claims (1)

[Claims] a talking circuit, a transmitter, a handset, a speaking pad inserted between the handset and the speaking circuit to adjust the speaking level, and a speaking pad inserted between the handset and the speaking circuit to adjust the speaking level; a receiving pad that adjusts the transmitting pad, a transmitting switching switch circuit that short-circuits and opens the input and output of the transmitting pad, and a receiving switching switch circuit that short-circuits and opens the input and output of the receiving pad; 1. A telephone circuit comprising a control circuit that short-circuits the transmitting switch circuit and the receiving switch circuit only by a signal sent when an outside line dialing key is pressed by keyboard operation.