GB1372905A - Apparatus for tesring data modems which simultaneously transmit and receive freuquency multiplexed signals - Google Patents

Apparatus for tesring data modems which simultaneously transmit and receive freuquency multiplexed signals

Info

Publication number
GB1372905A
GB1372905A GB5248472A GB5248472A GB1372905A GB 1372905 A GB1372905 A GB 1372905A GB 5248472 A GB5248472 A GB 5248472A GB 5248472 A GB5248472 A GB 5248472A GB 1372905 A GB1372905 A GB 1372905A
Authority
GB
United Kingdom
Prior art keywords
hybrid coupler
signals
tesring
freuquency
receive
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.)
Expired
Application number
GB5248472A
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.)
Milgo Electronic Corp
Original Assignee
Milgo Electronic 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 Milgo Electronic Corp filed Critical Milgo Electronic Corp
Publication of GB1372905A publication Critical patent/GB1372905A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/24—Testing correct operation
    • H04L1/242—Testing correct operation by comparing a transmitted test signal with a locally generated replica
    • H04L1/243—Testing correct operation by comparing a transmitted test signal with a locally generated replica at the transmitter, using a loop-back
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received

Abstract

1372905 Digital transmission; testing MILGO ELECTRONIC CORP 14 Nov 1972 [15 Nov 1971] 52484/72 Heading H4P In a testing arrangement for a FSK duplex system in which sending and receiving operates in different frequency bands, test signals are transmitted to a line where they are translated to the other band and returned for checking. At a terminal signals from a test pattern generator 20 are modulated into FSK form and transmitted through a hybrid coupler 26 to a balanced modulator 24 also receiving A.C. from a signal generator 28 translating them to the other frequency band which are passed through filter 30 and returned through hybrid coupler 26 to the receiver portion where they are analysed at 22. The hybrid coupler 26 includes directional amplifiers (70, 72) connected in an arrangement illustrated in greater detail in Fig. 4 (not shown). Signals formed in generator 28 may originate as a stepped waveform produced by a set of resistors cyclically switched at the input of an amplifier (47) (see Figs. 2 and 3, not shown).
GB5248472A 1971-11-15 1972-11-14 Apparatus for tesring data modems which simultaneously transmit and receive freuquency multiplexed signals Expired GB1372905A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US19887671A 1971-11-15 1971-11-15

Publications (1)

Publication Number Publication Date
GB1372905A true GB1372905A (en) 1974-11-06

Family

ID=22735224

Family Applications (1)

Application Number Title Priority Date Filing Date
GB5248472A Expired GB1372905A (en) 1971-11-15 1972-11-14 Apparatus for tesring data modems which simultaneously transmit and receive freuquency multiplexed signals

Country Status (7)

Country Link
JP (2) JPS4980913A (en)
CA (1) CA970888A (en)
CH (1) CH565487A5 (en)
DE (1) DE2255651A1 (en)
FR (1) FR2161606A5 (en)
GB (1) GB1372905A (en)
SE (1) SE383080B (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2386202A1 (en) * 1977-03-31 1978-10-27 Cit Alcatel MODEMS local test system in duplex telephone line - converts transmitters frequencies using modulator and local oscillator
EP0014583A1 (en) * 1979-02-13 1980-08-20 Macwell Systems Limited Improvements in or relating to fault-finding apparatuses
JPH083074Y2 (en) * 1989-06-15 1996-01-29 松下電工株式会社 Remote controller for television receiver

Also Published As

Publication number Publication date
CH565487A5 (en) 1975-08-15
SE383080B (en) 1976-02-23
JPS56104260U (en) 1981-08-14
DE2255651A1 (en) 1973-05-24
JPS4980913A (en) 1974-08-05
CA970888A (en) 1975-07-08
FR2161606A5 (en) 1973-07-06

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee