CA503448A - Voice frequency signalling systems - Google Patents

Voice frequency signalling systems

Info

Publication number
CA503448A
CA503448A CA503448A CA503448DA CA503448A CA 503448 A CA503448 A CA 503448A CA 503448 A CA503448 A CA 503448A CA 503448D A CA503448D A CA 503448DA CA 503448 A CA503448 A CA 503448A
Authority
CA
Canada
Prior art keywords
voice frequency
signalling systems
frequency signalling
systems
voice
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
CA503448A
Other languages
French (fr)
Inventor
F. S. Hargreaves Thomas
J. Terry Victor
Frederick William
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.)
International Standard Electric Corp
Original Assignee
International Standard Electric Corp
Publication date
Application granted granted Critical
Publication of CA503448A publication Critical patent/CA503448A/en
Expired legal-status Critical Current

Links

CA503448A Voice frequency signalling systems Expired CA503448A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CA503448T

Publications (1)

Publication Number Publication Date
CA503448A true CA503448A (en) 1954-06-01

Family

ID=35649363

Family Applications (1)

Application Number Title Priority Date Filing Date
CA503448A Expired CA503448A (en) Voice frequency signalling systems

Country Status (1)

Country Link
CA (1) CA503448A (en)

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