×

Remote supervising apparatus

  • US 4,314,101 A
  • Filed: 12/10/1979
  • Issued: 02/02/1982
  • Est. Priority Date: 12/10/1979
  • Status: Expired due to Term
First Claim
Patent Images

1. Apparatus for remotely supervising, via a telephone line, a device comprising:

  • sensing means for sensing for a telephone ring signal from the telephone line;

    means operative when said sensing means senses a telephone ring signal for simulating an off-hook condition in order to terminate the telephone ring signal;

    indicating means operative when said sensing means senses a telephone ring signal and after said off-hook condition is simulated for repeatedly producing a melody to form a series of melodies;

    said melody being at least one tone signal;

    means for transmitting said series of melodies to the telephone line;

    counting means for counting the melodies in the series as they are produced;

    key memory means connected to said telephone line and to said counting means for recording the presence or absence of a voice signal on the telephone line when a predetermined count has been counted by said counting means; and

    control means responsive to said key memory means for emitting a signal which changes the condition of the device if said key memory means recorded the presence of a voice signal on the telephone line when said predetermined count occurred.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×