Patent Yard Sign in
Expired Canadian patentCanada

Compatible am broadcast/data transmission system

CA 1252514 A · Owner: Kahn, Leonard R. · Inventors: Kahn, Leonard R.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A system for transmitting a composite signal comprising a data transmission signal component and an AM broadcast signal component. The broadcast signal component may be monophonic or stereophonic. The level of the data signal component is made a function of the modulation level so that the data signal is masked by the program modulation and, therefore, AM radio listeners will not be disturbed by the data signal. The rate of data transmission is reduced as the level of the data signal is reduced. The data signal is in quadrature with the AM carrier so as to minimize detection of the data signal by an envelope demodulator. Suitable data receivers are also disclosed.

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted April 11, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 11, 2006.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 24, 1985
GrantedApril 11, 1989
Term endedApril 11, 2006
Patent numberCA 1252514 A
Classification (IPC)H04J1/02

Timeline

Timeline From CIPO dates

1986198919921995199820012004Application filedMay 24, 1985Patent grantedApril 11, 1989Term endedApril 11, 2006

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.