JPS642451A - Incoming tone generating circuit - Google Patents

Incoming tone generating circuit

Info

Publication number
JPS642451A
JPS642451A JP15642187A JP15642187A JPS642451A JP S642451 A JPS642451 A JP S642451A JP 15642187 A JP15642187 A JP 15642187A JP 15642187 A JP15642187 A JP 15642187A JP S642451 A JPS642451 A JP S642451A
Authority
JP
Japan
Prior art keywords
signal
time
incoming tone
frequency
call signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP15642187A
Other languages
Japanese (ja)
Other versions
JPH012451A (en
Inventor
Makoto Shimizu
Tsutomu Ikeda
Osamu Shinohara
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Telegraph and Telephone Corp
Original Assignee
Nippon Telegraph and Telephone Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Telegraph and Telephone Corp filed Critical Nippon Telegraph and Telephone Corp
Priority to JP15642187A priority Critical patent/JPS642451A/en
Publication of JPH012451A publication Critical patent/JPH012451A/en
Publication of JPS642451A publication Critical patent/JPS642451A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE: To accurately identify the position of a telephone set which generates an incoming tone by varying the attribute of the incoming tone according to variation in time.
CONSTITUTION: A time monitoring circuit 7 monitors the time when a call signal detecting circuit 6 detects a call signal according to a frequency-divided signal from a frequency divider for a detection signal from the call signal detecting circuit 6 and a decoder 4 supplies a time variation decoding signal which varies with time to a programmable counter 5. Consequently, the signal of frequency indicated with the time variation decoding signal from the decoder 4 according to the elapsed time from the detection of the call signal by the call signal detecting circuit 6, i.e. an incoming tone signal varying in frequency with the elapsed time is generated. Thus, which telephone set there is an incoming signal to is accurately discriminated.
COPYRIGHT: (C)1989,JPO&Japio
JP15642187A 1987-06-25 1987-06-25 Incoming tone generating circuit Pending JPS642451A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15642187A JPS642451A (en) 1987-06-25 1987-06-25 Incoming tone generating circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15642187A JPS642451A (en) 1987-06-25 1987-06-25 Incoming tone generating circuit

Publications (2)

Publication Number Publication Date
JPH012451A JPH012451A (en) 1989-01-06
JPS642451A true JPS642451A (en) 1989-01-06

Family

ID=15627383

Family Applications (1)

Application Number Title Priority Date Filing Date
JP15642187A Pending JPS642451A (en) 1987-06-25 1987-06-25 Incoming tone generating circuit

Country Status (1)

Country Link
JP (1) JPS642451A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6067865A (en) * 1997-07-10 2000-05-30 Palas Gmbh Partikel-Und Lasermebtechnik Method and device for determining particle size distribution in aerosol

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63311844A (en) * 1987-06-15 1988-12-20 Nec Corp Telephone set

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63311844A (en) * 1987-06-15 1988-12-20 Nec Corp Telephone set

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6067865A (en) * 1997-07-10 2000-05-30 Palas Gmbh Partikel-Und Lasermebtechnik Method and device for determining particle size distribution in aerosol

Similar Documents

Publication Publication Date Title
JPS6426293A (en) Coin detection means
JPS5480160A (en) Alarm electronic watch
JPS53149076A (en) Digital frequency detecting circuit
TW265500B (en)
JPS642451A (en) Incoming tone generating circuit
JPS5750021A (en) Periodic signal detector
ATE202253T1 (en) DEVICE FOR DERIVING A CLOCK SIGNAL FROM A SYNCHRONOUS SIGNAL AND VIDEO RECORDING DEVICE EQUIPPED WITH THE DEVICE
DE3173994D1 (en) Signal error detecting
JPS553238A (en) Reception frequency display system
JPS536074A (en) Electronic watch with alarm
JPS55114969A (en) Battery life detection system
JPS56150382A (en) Electronic watch
JPS5686309A (en) Pedometer
JPS5680921A (en) Automatic tuning circuit
JPS5664683A (en) Electronic time piece having alarm
JPS5541090A (en) Density judgment system for video information
JPS55106391A (en) Electronic watch
JPS56111335A (en) Detecting circuit for circuit control signal of radiotelephone set
JPS52140302A (en) Magnetic tape life decision system
JPS57207496A (en) Dial pulse receiver
JPS57180261A (en) Digital tone receiver
JPS6469966A (en) Spotting apparatus of accident section for transmission line
JPS5764312A (en) Synchronizing signal circuit
JPS57208470A (en) Measuring device for frequency
JPS6427079A (en) Signal processing circuit