GB2124453A

GB2124453A - Telephone monitoring device

Info

Publication number: GB2124453A
Application number: GB08222032A
Authority: GB
Inventors: Shamshad Mohammed Khan
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-07-30
Filing date: 1982-07-30
Publication date: 1984-02-15

Abstract

A device for preventing mis-use of a telephone for making unauthorised long distance, direct dialled calls is responsive to dialling operations of the telephone and serves to prevent connection to the intended destination and/or produce a warning signal if the dialling operations signify use of the telephone to call an unauthorised destination.

Description

SPECIFICATION Telephone monitoring device This invention relates to a telephone monitoring device.

Nowadays, it is possible to make calls to many destinations within the UK and internationally by direct dialling, i.e. without the intervention of a telephone operator. This gives rise to the possibility of abuse in that, for example, people working in offices can make personal long distance calls without permission from and at the expense of the actual subscriber. Moreover, the method of billing currently used by the Post Office does not discriminate between local and long distance direct dialled calls which means that the subscriber cannot ascertain the extent of unauthorised use of the office telephone.

The object of the present invention is to provide a solution to the above problem and accordingly there is provided a device for preventing mis-use of a telephone for making unauthorised long distance, direct dialled calls, said device, when used in conjunction with the telephone, being responsive to the dialling operations carried out during the course of dialling a telephone number and being operable, if the dialling operations signify use of the telephone to call an unauthorised destination, to prevent connection to the intended destination and/or produce a warning signal to draw attention to the mis-use of the telephone.

As used herein, the term "dialling operation" is to be understood to refer to selection of digits either by operation of a rotary dial or by operation of keyboard switches of, for example, the pushbutton type.

The device is preferably electrically responsive to the dialling operations, for instance by detecting the pulse train produced as a result of each dialling operation. Conceivably however the device may be mechanically or electromechanically responsive to each dialling operation. Thus, for example, the device may mechanically register each time the telephone dial or a telephone push-button is operated.

Alternatively, each dialling operation may cause mechanical actuation of a switch or switches forming part of the device.

In a presently preferred embodiment, the device conveniently incorporates means for counting the dialling operations and means for preventing connection and/or producing a warning signal if, during the course of dialling an intended destination, the count reaches or exceeds a predetermined value. Thus, for example, if the subscriber wishes to restrict use of the telephone to local calls (which may for example be seven digit numbers or less) then the device may be preset by the subscriber to a count value of seven (or less), the arrangement being such that the connection preventing/signal producing means is rendered operable if the counter registers more than seven digits.

The count value preselected by the user will in general vary according to the area to which use of the telephone is to be restricted. For example, the area in question may be local (i.e. call destinations which do not need to be preceded by a STD code) in which event the preselected count value will be seven digits for many large cities, such as Birmingham, and less for many other localities. If the subscriber is concerned only to prevent unauthorised international direct dialling, then a preselected count value of ten digits will, in general, suffice.

The device is preferably of an electronic nature and may comprise circuitry which can be connected into the telephone dialling circuit to detect the pulse train produced by each dialling operation. The detector circuit may clock an electronic counter one step in response to each dialling operation and means may be provided for comparing the count registered by the counter with a preset count value entered by the user, e.g.

by way of a rotary thumbwheel switch or such like, so that when a count is reached which signifies unauthorised use of the telephone, the dialling circuit is disabled by the device to prevent onward transmission of any further digits dialled, thereby preventing completion of the telephone number of the intended destination. In addition, or alternatively, the dialling of further digits may lead to the production of a warning signal to alert the subscriber to mis-use of the telephone.

The counter of the device will be reset each time the handset of the telephone is replaced or lifted. The device conveniently includes means, such as an on-off switch, for disabling the device when this is required, e.g. when the subscriber wishes to make calls of a nature which are normally prevented by the device.

From the foregoing, it will be seen that the invention provides a monitoring device which is particularly effective in preventing unauthorised use of a telephone and which may be economical to manufacture and simple to install since the electronics of the device may be embodied in a microchip.

1. A device for preventing mis-use of a telephone for making unauthorised long distance, direct dialled calls, said device, when used in conjunction with the telephone, being responsive to the dialling operations carried out during the course of dialling a telephone number and being operable, if the dialling operations signify use of the telephone to call an unauthorised destination, to prevent connection to the intended destination and/or produce a warning signal to draw attention to the mis-use of the telephone.

2. A device as claimed in Claim 1 , the device being electrically responsive to dialling operations.

3. A device as claimed in Claim 2, the device being responsive to the pulse train produced as a result of each dialling operation.

4. A device as claimed in Claim 1, the device being mechanically or electromechanically responsive to each dialling operation.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Telephone monitoring device This invention relates to a telephone monitoring device. Nowadays, it is possible to make calls to many destinations within the UK and internationally by direct dialling, i.e. without the intervention of a telephone operator. This gives rise to the possibility of abuse in that, for example, people working in offices can make personal long distance calls without permission from and at the expense of the actual subscriber. Moreover, the method of billing currently used by the Post Office does not discriminate between local and long distance direct dialled calls which means that the subscriber cannot ascertain the extent of unauthorised use of the office telephone. The object of the present invention is to provide a solution to the above problem and accordingly there is provided a device for preventing mis-use of a telephone for making unauthorised long distance, direct dialled calls, said device, when used in conjunction with the telephone, being responsive to the dialling operations carried out during the course of dialling a telephone number and being operable, if the dialling operations signify use of the telephone to call an unauthorised destination, to prevent connection to the intended destination and/or produce a warning signal to draw attention to the mis-use of the telephone. As used herein, the term "dialling operation" is to be understood to refer to selection of digits either by operation of a rotary dial or by operation of keyboard switches of, for example, the pushbutton type. The device is preferably electrically responsive to the dialling operations, for instance by detecting the pulse train produced as a result of each dialling operation. Conceivably however the device may be mechanically or electromechanically responsive to each dialling operation. Thus, for example, the device may mechanically register each time the telephone dial or a telephone push-button is operated. Alternatively, each dialling operation may cause mechanical actuation of a switch or switches forming part of the device. In a presently preferred embodiment, the device conveniently incorporates means for counting the dialling operations and means for preventing connection and/or producing a warning signal if, during the course of dialling an intended destination, the count reaches or exceeds a predetermined value. Thus, for example, if the subscriber wishes to restrict use of the telephone to local calls (which may for example be seven digit numbers or less) then the device may be preset by the subscriber to a count value of seven (or less), the arrangement being such that the connection preventing/signal producing means is rendered operable if the counter registers more than seven digits. The count value preselected by the user will in general vary according to the area to which use of the telephone is to be restricted. For example, the area in question may be local (i.e. call destinations which do not need to be preceded by a STD code) in which event the preselected count value will be seven digits for many large cities, such as Birmingham, and less for many other localities. If the subscriber is concerned only to prevent unauthorised international direct dialling, then a preselected count value of ten digits will, in general, suffice. The device is preferably of an electronic nature and may comprise circuitry which can be connected into the telephone dialling circuit to detect the pulse train produced by each dialling operation. The detector circuit may clock an electronic counter one step in response to each dialling operation and means may be provided for comparing the count registered by the counter with a preset count value entered by the user, e.g. by way of a rotary thumbwheel switch or such like, so that when a count is reached which signifies unauthorised use of the telephone, the dialling circuit is disabled by the device to prevent onward transmission of any further digits dialled, thereby preventing completion of the telephone number of the intended destination. In addition, or alternatively, the dialling of further digits may lead to the production of a warning signal to alert the subscriber to mis-use of the telephone. The counter of the device will be reset each time the handset of the telephone is replaced or lifted. The device conveniently includes means, such as an on-off switch, for disabling the device when this is required, e.g. when the subscriber wishes to make calls of a nature which are normally prevented by the device. From the foregoing, it will be seen that the invention provides a monitoring device which is particularly effective in preventing unauthorised use of a telephone and which may be economical to manufacture and simple to install since the electronics of the device may be embodied in a microchip. CLAIMS

5. A device as claimed in any one of Claims 1-4 incorporating means for counting the dialling operations and means for preventing connection and/or producing a warning signal if, during the course of dialling an intended destination, the count reaches or exceeds a predetermined value.

6. A device as claimed in Claim 5, the device being presettable by the user to a predetermined count value and the arrangement being such that the connection preventing/signal producing means is rendered operable if the counter registers more than preset count value.

7. A device as claimed in Claim 1 , the device being of an electronic nature and comprising circuitry which can be connected into the telephone dialling circuit to detect the pulse train produced by each dialling operation.

8. A device as claim3d in Claim 7 in which the detector circuit is arranged to clock an electronic counter one step in response to each dialling operation and means is provided for comparing the count registered by the counter with a preset count value entered by the user so that when a count is reached which signifies unauthorised use of the telephone, the dialling circuit is disabled by the device to prevent onward transmission of any further digits dialled, thereby preventing completion of the telephone number of the intended destination.

9. A device as claimed in Claim 8 wherein dialling of further digits results in the production of a warning signal to alert the subscriber to mis-use of the telephone.

10. A device as claimed in Claim 7, 8 or 9 in which the counter of the device will be reset each time the handset of the telephone is replaced or lifted.

11. A device as claimed in any one of Claims 1-1 0 including means for disabling the device when this is required.

12. A device for preventing mis-use of a telephone for making unauthorised long distance, direct dialled calls, substantially as herein described.