Telephone nuisance call mitigation screening device

• US 5,157,712 A
• Filed: 03/13/1990
• Issued: 10/20/1992
• Est. Priority Date: 03/13/1990
• Status: Expired due to Fees

• Current Assignee: James Wallen Jr
• Original Assignee: James Wallen Jr
• Inventors: Wallen, James Jr.
• Primary Examiner(s): Levy, Stuart S.
• Assistant Examiner(s): Rhoa, Joseph A.
• Application Number:
  US07/492,761
• Time in Patent Office: 952 Days
• Field of Search: 379/77, 379/74, 379/199, 379/67, 379/68, 379/75, 379/76, 379/70
• US Class Current: 379/74
• CPC Class Codes: H04M 1/654 Telephone line monitoring circuits therefor, e.g. ring detectors
• CPC Class Codes: H04M 1/665 by checking the validity of a code
• CPC Class Codes: Y10S 379/903 Password

Abstract

A telephone nuisance call mitigation device operates in conjunction with an answering machine. The usual ringer of the user'"'"'s telephone(s) is deactivated. The answering maching produces a message which instructs the user to enter his secret code if he has it or else just to leave a message after the tone. The mitigation device monitors for the proper secret code being entered, and if received produces an off hook and a ringing tone in the user'"'"'s home for a predetermined period. Otherwise, the user can only leave a message, and a ringing tone will never be provided to the user'"'"'s house. Provision is also made for preventing erroneous detections during call out operations, and for resetting the system to maintain synchronization. The mitigation device is continuously parallel to the telephone line.

Claims

1. A telecommunications nuisance call mitigation device adapted for use with an answering machine of the type which plays a message to a caller indicating that the caller should enter a code, said mitigation device comprising:

means for recognizing whether a code entered after said message coincides with a preset code in said device;

timing means, responsive to said recognizing means, for beginning a predetermined time period after recognizing said code as coinciding with said preset code;

means, responsive to said timing means, for producing an off hook indication to a central office, during said predetermined time period, and for producing a signal indicative of a non-nuisance call during said time period; and

means for connecting said recognizing means and said off hook indication producing means in parallel with a telephone line at all times after installation with the telephone line.

2. A device as in claim 1 wherein said signal indicative of said non-nuisance call is a ringing tone to a user, and said recognizing means includes means for recognizing a plurality of different touch-tone type characters and means for recognizing a predetermined sequence of predetermined ones of said touch tone characters as said preset code.

3. A device as in claim 2 wherein one of said touch tone characters represents an initialization character and wherein said timing means is responsive to said recognizing means and is reset upon said recognizing means recognizing said initialization character.

4. A device as in claim 3 wherein said predetermined sequence of touch tone characters includes one exclusion character which is not normally used during placing telephone calls.

5. A device as in claim 4 wherein said recognizing a predetermined sequence means includes at least one switchable device which is switchable to determine which of a plurality of said characters represents a set character, and includes counter means, responsive to a digit detect output of said recognizing means, for counting a number of digit detects which have been produced and producing a count output indicative thereof, and means for determining if a set character, set by said switching device, is produced at a predetermined count indicated by said counter means, and producing a code detect output when all proper digits are located during proper counts.

6. A device as in claim 5 wherein said counter means and said determining means are also reset upon recognition of said initialization character.

7. A device as in claim 2 wherein said predetermined sequence of touch tone characters includes one exclusion character which is not normally used during placing telephone calls.

8. A nuisance call mitigation device, adapted to operate with a plurality of telephone which have ringers that are, at least initially, disconnected, comprising:

an answering machine, having a message recorded thereon indicating that a user should either enter the identification code or record a message after the tone;

digit detecting means, coupled to a telephone line, for detecting digits input therefrom;

logic means, coupled to said digit detecting means, for recognizing a predetermined sequence of predetermined ones of said digits to recognize a proper code only after said answering machine has played said message;

line supervision and annunciating means, coupled to said logic means, for holding the telephone line open and annunciating an incoming call to the user, only for a predetermined time after said logic means determines that a proper code has been entered; and

means for connecting said answering machine, said digit detecting means, said logic means and said line supervision and annunciating means in parallel with the telephone line at all times after installation with the telephone line.

9. A device as in claim 8 wherein said line supervision and annunciating means includes a relay and a resistor, said relay being closed to form a current path through said resistor across two wires constituting said telephone line to produce an off hook condition to hold said telephone line.

10. A device as in claim 9 wherein said digit detecting means is a DTMF receiver.

11. A device as in claim 10 wherein said logic means includes a plurality of switch arrays, each array being set with at least one of said codes, and means for determining if the proper code is produced during a cycle of operation to which it is associated.

12. A device as in claim 8 wherein said digit detecting means detects one of said characters as being an initialization character, and resets said logic means and said line supervision and annunciating means when said initialization character is detected.

13. A device as in claim 12 wherein said digit detecting means detects one of said digits as being an exclusion code, which is one not normally entered to access outgoing telephone numbers, and wherein said logic means includes means for detecting said exclusion code as a necessary part of said proper code.

14. A device as in claim 8 wherein said digit detecting means detects one of said digits as being an exclusion code as a necessary part of said identification code, which is one not normally entered to access outgoing telephone numbers, and wherein said logic means includes means for detecting said exclusion code as a necessary part of said proper codes.

15. A method of mitigating unwanted nuisance calls, comprising the steps of:

an initial step of connecting a logic module and an answering machine in parallel with a telephone line, and thereafter maintaining said logic module and said answering machine in parallel with the telephone line at all times;

recording a message on said answering machine indicating that if the incoming caller has an identification code to enter it, or else to leave a message;

playing said message in response to an incoming call;

after said playing step, receiving incoming signals from a telephone line;

determining if the incoming signals coincide with a pre-stored sequence of signals forming a predetermined code;

starting a timer if the incoming code coincides with the prestored predetermined code;

producing an off hook signal to the central office while said timer is running; and

operating a telephone call annunciation to the user while said timer is running, and wherein said receiving, determining, starting, producing and operating steps are carried out by said logic module.

16. A method as in claim 15 comprising the further step of resetting said timer upon detecting a predetermined digit.

17. A method as in claim 15 wherein said method is used with at least one telephone, and comprising the further step of, prior to said receiving incoming signals step, preventing said at least one telephone from ringing due to said incoming signals.

18. A nuisance call mitigation device adapted for use with an answering machine of the type which plays a message to a user indicating that the user should enter a code after an indication, said mitigation device comprising:

a DTMF receiver for recognizing touch tone digits including a digit indicative of reset, and for producing a digit detect signal each time one of said touch tone digits is recognized as well as producing a code indicative of which of said touch tone digits is recognized;

decoder means, receiving said indicative codes, for producing a plurality of outputs, one indicative of each said predetermined code which is received;

code setting means, connected to at least a plurality of said outputs of said decoding means, and switchable to determine which of said outputs is a proper code to be recognized;

counter means, connected to be advanced in count by said digit detect signal, for determining a cycle of operation indicative of how many digits have been detected by said DTMF receiver, and producing a plurality of count outputs indicative thereof;

a plurality of logic means, connected to one of said count outputs, and to outputs of said code setting means, each logic means for producing an active output when said code setting means produces an active output simultaneously with said counter means producing an active output on said one count output to which it is connected;

a plurality of latching means, each connected to an output of said logic means, for latching an indication that said logic means has produced an active output;

means for detecting when all of said latching means are active, and producing a code detect signal indicative thereof;

first timing means, responsive to said code detect signal, for producing a time period beginning at said code detect signal;

means for sending an off hook signal to the central office during said time period;

annunciating means for producing an annunciating tone at a user during said time period;

means for resetting both of said latching means and said timing means upon receiving said reset digit; and

means for connecting said DTMF receiver and said sending means in parallel with a telephone line at all times after installation with the telephone line.

19. A system as in claim 18 further comprising first timing means, responsive to said code detect signal, for producing a time period beginning at said code detect signal;

means for sending an off hook signal to the central office during said time period; and

annunciating means for producing an annunciating tone during said time period.

20. A system as in claim 19 wherein said logic means comprises a plurality of AND gates each having one input connected to an output of said counter means, and with its other input to an output of said code setting means.

21. A system as in claim 20 wherein said code setting means comprises a plurality of switches, each connected to a respective one of said outputs of said decoder means.

22. A system as in claim 21 wherein said detecting means comprises a multiple input AND gate.

23. A system as in claim 19 wherein one of the digits recognized by said DTMF receiver represents a reset digit, further comprising means for resetting both of said latching means and said timing means upon receiving said reset digit.

24. A system as in claim 18 further comprising an auxiliary latching means, responsive to a detection of an exclusion code, which is a code not normally dialed during touch tone calling operation, and which occurs at the same time as a predetermined cycle of said counter means, and wherein said detecting means is responsive to said auxiliary latching means, and produces said code detect signal only when said latching means and said auxiliary latching means are all simultaneously active.

25. A system as in claim 18 further comprising:

an auxiliary latching means, responsive to a detection of an exclusion code, which is a code not normally dialed during touch tone calling operation, and which occurs at the same time as a predetermined cycle of said counter means, and wherein said detecting means is responsive to said auxiliary latching means, and produces said code detect signal only when said latching means and said auxiliary latching means are all simultaneously active.

26. A system as in claim 25 wherein said exclusion code is a code from the group consisting of "#" and "*".

27. A telecommunications nuisance call mitigation device adapted for use with an answering machine of the type which plays a message to a caller indicating that the caller should enter a code, said mitigation device comprising:

means for recognizing a plurality of different touch-tone type characters;

code recognizing means for recognizing a predetermined sequence of predetermined ones of said touch tone characters, including one exclusion character which is not normally used during placing telephone calls, as a preset code;

timing means, responsive to said recognizing means, for beginning a predetermined time period after recognizing said code as coinciding with said preset code;

means, responsive to said timing means, for producing an off hook indication to a central office, during said predetermined time period, and for producing a signal indicative of a non-nuisance call during said time period; and

means for connecting said recognizing means and said off hook indication producing means in parallel with a telephone line at all times after installation with the telephone line.

28. A telecommunications nuisance call mitigation device, comprising:

an answering machine configured to play a message to a caller indicating that the caller should enter a code;

means for recognizing whether a code entered after said message coincides with a preset code;

timing means, responsive to said recognizing means, for beginning a predetermined time period after recognizing said code as coinciding with said preset code;

means, responsive to said timing means, for producing an off hook indication to a central office, during said predetermined time period, and for producing a signal indicative of a non-nuisance call during said time period; and

means for connecting said answering machine, said recognizing means and said off hook indication producing means in parallel with a telephone line at all times after installation with the telephone line.

29. A telecommunications nuisance call mitigation device adapted for use on a telephone line across two lines of which codes can be entered, and for use with an answering machine of the type which plays a message to a caller indicating that the caller should enter a code, said mitigation device comprising:

means, adapted to be continuously coupled in parallel across said two lines of said telephone line, for recognizing whether a code entered after said message is played coincides with a preset code;

timing means, responsive to said recognizing means, for beginning a predetermined time period after recognizing said code as coinciding with said preset code; and

means, responsive to said timing means and adapted to be continously coupled in parallel across said two lines of said telephone line, for producing an off hook indication to said telephone line, during said predetermined time period, and for producing a signal indicative of a non-nuisance call during said time period.