JPS5793736A - Tone squelch monitoring system - Google Patents

Tone squelch monitoring system

Info

Publication number
JPS5793736A
JPS5793736A JP55170349A JP17034980A JPS5793736A JP S5793736 A JPS5793736 A JP S5793736A JP 55170349 A JP55170349 A JP 55170349A JP 17034980 A JP17034980 A JP 17034980A JP S5793736 A JPS5793736 A JP S5793736A
Authority
JP
Japan
Prior art keywords
tone
group
receiver
demodulation signal
discrimination
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
JP55170349A
Other languages
Japanese (ja)
Inventor
Akio Nakanishi
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP55170349A priority Critical patent/JPS5793736A/en
Publication of JPS5793736A publication Critical patent/JPS5793736A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
    • H04B1/40—Circuits

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transceivers (AREA)
  • Noise Elimination (AREA)

Abstract

PURPOSE:To prevent the production of crosstalk due to simultaneous transmission, by the generation of busy tone during busy state of other group and informing the busy state to the operator. CONSTITUTION:When an incoming call of group itself is given to an antenna 8, a demodulation signal from a receiver 9 is inputted to a tone squelch circuit 10, which detects the tone for group discrimination and selects a squelch 13 to (a) side. Thus, the demodulation signal from the receiver 9 is applied to a speaker 15 via an audio band pass filter 11 and a low-frequency amplifier 14 to receive the call of group. In case of incoming call of other group, the tone squelch circuit 10 detects the tone of other group discrimination, the switch 13 is changed over to (b) side, and a demodulation signal from the receiver 9 is applied to the speaker 15 via a discrimination band pass filter 12 and the low-frequency amplifier 14 to transmit continuous tone.
JP55170349A 1980-12-03 1980-12-03 Tone squelch monitoring system Pending JPS5793736A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP55170349A JPS5793736A (en) 1980-12-03 1980-12-03 Tone squelch monitoring system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP55170349A JPS5793736A (en) 1980-12-03 1980-12-03 Tone squelch monitoring system

Publications (1)

Publication Number Publication Date
JPS5793736A true JPS5793736A (en) 1982-06-10

Family

ID=15903275

Family Applications (1)

Application Number Title Priority Date Filing Date
JP55170349A Pending JPS5793736A (en) 1980-12-03 1980-12-03 Tone squelch monitoring system

Country Status (1)

Country Link
JP (1) JPS5793736A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62159521A (en) * 1985-12-20 1987-07-15 インタ−ナシヨナル・スタンダ−ド・エレクトリツク・コ−ポレイシヨン Digital tone squelch detector

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62159521A (en) * 1985-12-20 1987-07-15 インタ−ナシヨナル・スタンダ−ド・エレクトリツク・コ−ポレイシヨン Digital tone squelch detector
JPH0517730B2 (en) * 1985-12-20 1993-03-10 Intaanashonaru Sutandaado Erekutoritsuku Corp

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