WO1990016119A1

WO1990016119A1 - Cable identification system and method

Info

Publication number: WO1990016119A1
Application number: PCT/US1990/003375
Authority: WO
Inventors: Brent A. James; Lewis G. James
Original assignee: James Brent A
Priority date: 1989-06-14
Filing date: 1990-06-13
Publication date: 1990-12-27
Also published as: AU5857690A

Abstract

A cable identification system and method for cable communication installation for multiple reception units including communications receivers (10, 10', 10') in the reception units each connected by one of a plurality of branch cables (12, 12', 12') joined at a central distribution unit (14) to a signal source or destination, wherein an electronic programmable-readable cable identifier (20) is provided in each of a plurality of the branch cables (12, 12', 12') adjacent the corresponding receivers (10, 10', 10'), and a hand-held programmer-reader (30) is used to program a unique identifying address into a selected identifier and also is used to subsequently read the address by applying an activation signal to the branch cable (12) containing the identifier (20) and receiving a signal from the identifier (20) containing said address which is displayed (38) in the hand-held programmer-reader (30).

Description

CABLE IDENTIFICATION SYSTEM AND METHOD

Technical Field

This invention relates to the wire communications art, and more particularly to a new and improved cable identification system and method for cable television installations and the like. Background Of The Invention

One area of use of the present invention is in cable television installations for multiple dwelling units, although the principles of the present invention can be variously applied. A typical example of such installation is a large apartment building including a considerable number of subscriber television receivers in various apartments connected by a corresponding number of branch cables to a distribution box, typically located in the basement of the building which box, in turn, is connected to the main input cable providing communications signals for distribution to the receivers. For installation and maintenance procedures, the branch cables must have individual subscriber identification at the distribution box, otherwise time and labor intrusive ringing out procedures would be required at the onset of each installation or maintenance procedure. A common means of identification is a label or tag physically attached externally to each cable. However, a significant problem with this form of identification is physical removal of the tags or labels by accident or vandalism.

Objects and Summary Of The Invention It would, therefore, be highly desirable to provide a new and improved cable identification system and method for multiple reception units wherein the cable identification cannot be removed by unauthorized manual or other physical means, is easy to install and readily changeable by installation and maintenance personnel, and is quickly and easily readable. The present invention provides a cable identification

UBSTITUTE SWtf system and method for a cable communication installation for multiple reception units including communications receivers in the reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a single main cable from a source of communications signals wherein an electronic programmable-readable cable identifier is provided in each of a plurality of branch cables, a unique identifying address is programmed into each of the identifiers, and subsequently an address is read by applying an activation signal through a selected branch cable to the identifier in that cable and receiving a signal from that identifier containing the address. Preferably the cable identifier is located in the branch cable adjacent the reception unit and the address is read at a location on the branch cable adjacent the distribution unit. Each of the electronic programmable-readable identifiers comprises means for receiving a programming message signal applied thereto containing a unique identifying address, means for storing the unique identifying address and means for transmitting a signal containing the unique identifying address along the branch cable toward the distribution unit in response to an activation signal applied thereto so that the unique identifying address can be read at a location remote from the reception unit such as on the end of the branch cable at the central distribution unit. A single programmer-reader device is provided comprising computer means having an input adapted to be connected to any selected branch cable for receiving a signal containing the unique identifying address from the cable identifier in that selected branch cable in response to an activation signal, a first output for providing address information associated with the cable identifier and a second output for providing a programming message signal for supplying a unique identifying address for any selected cable identifier, readout means connected to the first output of the computer means for providing information as to the address read from a selected

SHEET -3-

identifier and as to the address programmed into a selected identifier, and means for connecting the second output of the computer means to any selected cable identifier for applying , the programming message signal thereto. Preferably the device is contained in a housing which is small in size and light in weight so as to be hand-held and portable.

The foregoing will become more apparent upon a reading of the ensuing detailed description together with the accompanying drawings in which a preferred form of this invention is illustrated.

Brief Description Of The Drawings

Fig. 1 is a schematic diagram of a portion of a cable communication installation for multiple dwelling units and showing an electronic cable identifier according to the present invention in one of the branch cables of the installation;

Fig. 2 is a schematic diagram similar to Fig. 1 showing a programmer-reader device according to the present invention when applying a unique identifying address to a cable identifier;

Fig. 3 is a schematic diagram similar to Fig. 1 showing the programmer-reader device according to the present invention when reading the address from a cable identifier on one of the branch cables; Fig. 4 is a block diagram of the cable identifier of the cable identification system of the present invention;

Fig. 5 is a block diagram of the programmer-reader of the cable identification system of the present invention; and Fig. 6 is a schematic circuit diagram of the cable identification system of the present invention showing the programmer-reader connected to a cable identifier.

Detailed Description

In a basic cable communication installation for multiple reception units including communications receivers in the reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a single main cable from a source of communications signals, the branch cables heretofore have been identified by physical means, such as labels or tags attached externally thereto, with the potential problem of unwanted or unauthorized removal of the identification by accident or vandalism. In the cable identification system and method according to the present invention, an electronic programmable-readable cable identifier is provided in each of a plurality of branch cables, preferably in the reception unit, a hand-held programmer is used to apply a programming signal to the cable identifier to program a unique identifying address therein, and subsequently when address information is needed the hand-held programmer is employed to read the address of the identifier by applying an actuation signal to the branch cable, preferably adjacent the central distribution unit, and receiving a signal from the identifier containing the address.

Referring now to Fig. 1, there is shown a cable installation for multiple reception units, for example multiple dwelling units such as apartments. A plurality of communication receivers 10,10', and 10", such as television receivers, are in a corresponding plurality of reception units, i.e. multiple dwelling units. While only three receivers are shown for convenience, it is to be understood that in typical multiple reception units, such as a large apartment building or complex, a large number of receivers are included in the communication installation. Each receiver is connected to one end of a plurality of branch cables 12, 12',12", the other ends of which are connected through a central distribution unit 14 to a single main cable 16 from a source of communication signals, such as the cable television broadcast station. Distribution unit 14, commonly referred to as a distribution box, contains a multiport tap and plurality of F-connectors, as is well-known to those skilled in the art. In multiple dwelling units such as apartment buildings, distribution unit 14 typically is located in the basement.

In accordance with the present invention, an electronic cable identifier 20 is connected in each branch cable 12 to be identified and is at a location remote from central distribution unit 14, preferably in the corresponding reception unit. In the illustrative installation shown, a plurality of cable identifiers 20,20' and 20" are connected in the corresponding branch cables 12, 12' and 12", respectively. In a typical multiple dwelling unit installation, the cable identifier 20 would be located inside the wall through which branch cable 12 extends. The cable identifier 20 is responsive to a programming message signal for storing a unique identifying address and is responsive to an activation signal which prompts transmission of a signal containing the previously received identifying address along branch cable 12 toward distribution unit 14. Each cable identifier 20 can be contained in a relatively small cylindrical housing provided with F type connectors at each end for connection in the branch cable 12 and there is provided a separate connection or terminal to which the programming signal is applied in a manner which will be described. Regular cable television programming may be distributed to the receivers without interference by the cable identifier 20. Each cable identifier 20 is a passive device, in that it does not require any power source to maintain the unique identifying address stored therein.

The cable identification system of the present invention further comprises a single programmer-reader 30 having a first mode for applying programming message signals to individual ones of the cable identifiers 20 for storing unique identifying addresses in the identifiers and a second mode for reading the unique identifying address stored in any one of the cable identifiers when the programmer-reader is connected to the branch cable containing that particular identifier. Referring to Fig. 2, the programmer-reader 30 preferably is a hand-held -6-

device contained in a housing 32 which is small in size and light in weight so as to be hand-held and portable. Programmer-reader 30 is shown in Fig. 2 in the first mode of operation where it is connected to a selected cable identifier by conductor 34, a unique identifying address is entered^'by the installation or maintenance person on a keypad 36 of the device, the address is displayed visually on an address display 38 of the device and then a programming message signal is sent from device 30 to cable identifier 20 through conductor 34 so that the displayed unique identifying address is programmed into the cable identifier where it is retained indefinitely.

Referring now to Fig. 3, programmer-reader 30 is shown in the second mode of operation wherein it is connected to a branch cable 12 for reading the address in the identifier contained in that selected branch cable. At any time, the hand-held device may be connected to a branch cable 12 at the distribution box 14 in order to read the address of the remote location from the cable identifier 20 in that branch cable. When reading the cable identifier 20, the person inputs an appropriate command through keypad 36 causing the hand-held device 30 to send an activation signal along branch cable 12 until the unique identifying address is returned via a received signal whereupon the address is viewed on display 38. If no address is returned, the device 30 will indicate such to the user.

The cable identification system of the present invention, comprising a plurality of cable identifiers 20 and the programmer-reader 30, provides a complete means for identifying coaxial twisted pair and other cable assemblies in installation and maintenance situations that would otherwise require time and labor intensive ringing out procedures. The identification system can be used in cable television, broadband local area networks, star networks and other similar installations. The cable identification system and method of the present invention is not susceptible to unwanted or unauthorized physical removal of the identification such as by accident or vandalism, thereby avoiding problems associated with tags or labels externally physically attached to cables. The cable identification system and method of the present invention is easy to install and use by installation and maintenance personnel, provides such personnel with a quick and easy reading of the cable identification, and allows such personnel to readily change the identification when necessary.

Fig. 4 illustrates in further detail the cable identifier 20 of the present invention. It includes three major components: a microcomputer 44, a cable identifier power converter 46 and an address modulator 48. The power converter 46 is a current to voltage converter which supplies the necessary power for operating cable identifier 20. Alternatively, a continuous wave detector could be employed for applications requiring direct current isolation. The address modulator 48 converts an asynchronous logic signal from microprocessor 44 into current variations on branch cable 12. Alternatively, modulator 48 could be a frequency, phase or amplitude modulator depending on bandwidth limitations of the cabling and cost considerations. Microcomputer 44 provides the unique identifying address programmed therein as an output to address modulator 48. A logic level input is also used for reading the unique identifying address from hand-held programmer-reader 30 in an asynchronous format and saving it in non-volatile storage. The cable identifier 20 of Fig. 4 will be desccribed in further detail presently.

Fig. 5 illustrates in further detail the hand-held programmer-reader 30 of the present invention. It includes five major components: the keypad 36, the address display 38, a cable identifier activation source 52, an address demodulator 54 and a microcomputer 56. The keypad 36 takes user input from the cable installation or maintenance person for reading an address from a cable identifier 20 and for programming an address into a cable identifier. The address display 38 shows -8-

the unique identifying address following a cable identifier read operation. Display 38 also allows the user to show a new address before programming it into a cable identifier. The cable identifier activation source 52 is a current source for the cable identifier 20. It is necessary that source 52 provides an activation signal having sufficient power to activate the circuitry of cable identifier 20. Alternatively, a continuous wave source could be employed for applications requiring direct current isolation. Address demodulator 54 reads asynchronous current variations from the cable identifier 20 and converts them to logic levels readable by microcomputer 56. The microcomputer 56 takes inputs from keypad 36 and from address demodulator 54 and provides outputs to address display 33 and to cable identifier activation source 52. A logic level output also is provided on conductor 34 for programming the cable identifier 20.

Fig. 6 shows in further detail the components and circuits included in cable identifier 20 and hand-held programmer-reader 30 of the cable identification system. Cable identifier 20 has a first terminal 70, a second terminal 72 for connection to the portion of branch cable 12 leading to distribution box 14, and a third terminal 74 for connection to the portion of the branch cable leading to the reception unit, i.e. television receiver 10. During the mode of operation when a unique identifying address is programmed into cable identifier 20, conductor 34 from programmer-reader 30 is connected to terminal 70, and the signal path during programming is indicated by arrows 80 in Fig. 6. During the mode of operation when the address stored in cable identifier 20 is read by programmer-reader 30, terminal 70 is not connected, terminal 72 is connected to the one end of branch cable 12, and programmer-reader 30 is connected to the opposite end of branch cable 12, typically at distribution box 14. An activation signal is transmitted from programmer-reader 30 along branch cable 12 to power converter 46, and a signal containing the address stored in cable identifier 20 is transmitted along branch cable 12 into programmer-reader 30 in the direction indicated by arrows 82 in Fig. 6. During reception of television boradcast signals and the like, programmer-reader 30 of course is not connected and the signals travel along the portion of branch cable 12 between distribution box 14 and cable identifier 20, through a path between terminals 72 and 74, and along the portion of branch cable 12 between cable identifier 20 and the television receiver 10. Cable identifier 20 does not interfere with this reception of broadcast signals, this being assured by the filter network comprising inductors 86 and 88 and capacitor 90 shown in Fig. 6. Microcomputer 44 includes a microprocessor 94 and a programmable read-only memory 96, the two components being connected by lines 98. Terminal 70 is connected by line 100 to an input of microprocessor 94, and a quartz crystal 102 provides resonance for the internal clock of microprocessor 94. Address modulator 48 includes an NPN transistor 110, the base terminal of which is connected through a resistor 112 to an output of microprocessor 94, the emitter terminal of which is connected to an electrical reference or ground, and the collector terminal of which is connected through a resistor 116 to the output of address modulator 48. Power converter 46 includes the parallel combination of capacitor 118 and Zener diode 120 connected between the source of positive voltage +V and the electrical reference or ground. The junction of the cathode of Zener diode 120 and positive terminal of capacitor 118 is connected through a resistor 122 to the cathode of diode 124, the anode of which is connected through inductor 86 to cable identifier terminal 72. The junction of resistor 122 and diode 124 is connected to the output end of resistor 116 of address modulator 48. By way of example, in an illustrative circuit, capacitor 90 has a magnitude of 180 picofarads, microprocessor 94 is Motorola 68704P2 with Ice typically 35 ma and a maximum of 50

2 a, memory 96 is an E PROM designated EXCEL 93C46 with Ice having a maximum value of 3 ma. and a standby value of 0.4 ma, crystal 102 has a resonant frequency of 11 MHZ, capacitor 103 has a magnitude of 47 picofarads, each resistor 104,106 and 114 has a magnitude of 10 kilohms, capacitor 108 has a magnitude of

0.1 microfarad, transistor 110 is type 2N4401, resistors 112 and 116 have magnitudes of IK and 110 Ohm, respectively, capacitor 118 has a magnitude of 10 microfarads, Zener diode is type 1N4733 having a threshold voltage of 5.1 volts, and diode 124 is type 1N4148. The source of voltage +V has a magnitude of five volts.

Programmer-reader 30 includes a first terminal 130 which is connected to one end of conductor 34, the other end of which is adapted for connection to terminal 70 of cable identifier 20 during the programming mode as previously described. A second terminal 132 of programmer-reader 30 is adapted for connection to branch cable 12 for reading the address from a cable identifier as previously described. Microcomputer 56 comprises a microporcessor 136 having a quartz crystal 138 providing resonance for the internal clock of the microprocessor. The programming signal output from microprocessor 136 is connected by line 142 and a resistor 144 to terminal 130. The junction of line 142 and resistor 144 is connected through another resistor 146 to electrical ground.

In the illustrative device shown keypad 36 comprises a network of four switches 36a-36d and corresponding resistors 152a-152d connected to inputs of microprocessor 136 by lines 154. One of the switches can command a read mode, a second can command a programming mode, a third can increment the displayed address at the onset of programming and the fourth can decrement the displayed address at the onset of programming. Address display 38 comprises a pair of identical display elements 160 and 162. Lines 164 connect one output port of microprocessor 136 to display elements 160,162 and lines 168, -li¬

no, 172 and 174 connect another output port of microprocessor 136 to display elements 160 and 162.

Activation source 52 includes a voltage source in the form of battery 180, a voltage regulator 182 and a PNP transistor 184. The negative terminal of battery 180 is grounded and the positive terminal is connected through switch 186 and line 188 to the input of voltage regulator 182. A reference terminal of voltage regulator 182 is connected through the series combination of diodes 190 to electrical ground. The output of voltage regulator 182 is connected by line 194 to the emitter terminal of transistor 184 and the output also is connected to one terminal of a capacitor 196, the other teminal of which is grounded. The base terminal of transistor 184 is connected through the series combination of diodes 200 and line 202 to an output of microprocessor 136. A resistor 206 is connected between th base and emitter of transistor 184. The collector of transistor 184 is connected through a resistor 210 and line 212 to terminal 132. Another voltage regulator 216 is provided having an input connected by line 218 to line 188 and also connected to one terminal of a capacitor 220, the other terminal of which is grounded. The output is the source of positive bias voltage +V is connected and to one terminal of a capacitor 222, the other terminal of which is grounded. Thus, when it is desired to send an activation signal along branch cable 12 to a cable identifier 20, in response to depression of the appropriate keypad switch 36, microprocessor 136 provides an output signal on line 202 which turns on transistor 184 to apply the signal output of voltage regulator 182 to terminal 132. Address demodulator 54 includes a voltage comparator 230 having a pair of inputs 232,234 and an output 236. Input 232 is connected by line 240 to terminal 132 for receiving cable identifier address signals. The other input 234 is connected through a resistor 236 to ground. The address demodulator 54 uses a reference voltage provided by the combination of

S EE resistor 236, voltage reference 182 and diode 244, the anode of which is connected to the voltage reference 182 and the cathode of which is connected to comparator input terminal 234. The output 236 of comparator 230 is connected though a resistor 248 and line 250 to an input of microprocessor 136. A resistor 252 is connected from the junction of resistor 248 and line 250 to ground.

Microcomputer 56 is programmed to present characters in the display windows in response to pressing of keypad buttons 36, for example the characters 0-9 followed by A-Z. In particular, in response to pressing a first key 36a, the first display window is highlighted. Pressing the next key 36b starts display of the character and advances or increments the displayed character until the desired one appears whereupon the key is released and the desired character remains. Pressing the first key 36a then highlights the next display window whereupon the next key 36b is pressed as before to increment or advance the characters until the desired one is obtained. The foregoing procedure is repeated for each display window until the entire display is filled with the desired address. When all the windows of the display are filled, pressing the first key 36 a will cause the programming signal containing the address to be sent via conductor 34 to the cable identifier 20 to program the same. Another one of the keys, for example key 36c, can be used to decrement or reverse the displayed character in each display window. The remaining key, i.e. key 36d, is pressed during the read mode which causes generation of the activation signal for recording the address of a cable identifier 20. By way of example, in an illustrative circuit, microprocessor 136 is Motorola 68704P2, crystal 138 has a resonant frequency of 11 MHZ, capacitor 140 has a magnitudie of 47 picofarads, resistors 144, 146 and 148 have magnitudes of IK, 47K and 10K ohms, respectively, capacitor 150 has a magnitude of 0.1 microfarad, resistors 152a-d have magnitudes

SUBSTITUTE SHEET of 100K ohms, each display element 160,162 is of the type commercially available from Hewlett Packard under the designation HPDL-1414, battery 180 has a magnitude of 9 volts, pulse generators 182 and 216 are type 7805, transistor 184 is type 2N4403, diodes 190 are type 1N4148, capactior 196 has a magnitude of 0.1 microfard, diodes 200 are type 1N4148, resistor 204 has a magnitude of 100K, resistor 206 has a magnitude of 10K, resistor 210 has a magnitude of 15 ohms, capactiors 220 and 222 have magnitudes of 1 microfarad and 22 microfarads, respectively, amplifier 230 is type TL081, resistors 236 has a magnitude of 47K, diode 244 is type 1N4148, and resistors 248 and 252 have magnitudes of 39K and 22K, respectively. The source of voltage +V has a magnitude of five volts. What is claimed is:

SUBSTITUTE SHEET

Claims

1. A cable identification system for a cable communication installation for multiple reception units including communications receivers in said reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a signal source or destination said identification system comprising: a) a plurality of electronic cable identifiers each connected in a corresponding one of said branch cables for respective ones of said reception units, each of said identifiers being responsive to a programming message signal for storing a unique identifying address and being responsive to an activation signal for transmitting said identifying address on said cable toward said distribution unit; and b) a single programmer-reader having a first mode for applying programming message signals to individual ones of said cable identifiers for storing unique identifying addresses in said identifiers and a second mode for reading the unique identifying address stored in any one of said cable identifiers when said programmer-reader is connected to the branch cable containing that particular identifier.

2. The cable identification system according to claim 1, wherein each of said branch cables has an end removably connected to said distribution unit and wherein said programmer-identifier is connected to said end during said second mode.

3. The cable identification system according to claim 1, wherein each of said cable identifiers has a first terminal for connection to said programmer-reader during said first mode wherein a programming message signal is applied to said first terminal for storing a unique identifying address in said cable identifier, and wherein each of said cable identifiers has second and third terminals for connection to said branch cable.

4. The cable identification system according to claim 3, wherein each of said cable identifiers includes circuit means connected to said second and third terminals for preventing interference by said cable identifier with communications signals transmitted on said branch cable to said communications receiver.

5. The cable identification system according to claim 1, wherein each of said communications receivers is a television receiver.

6. The cable identification system according to claim 1, wherein said programmer-reader is contained in a housing which is small in size and light in weight so as to be hand-held and portable.

7. The cable identification system according to claim 1, wherein each of said cable identifiers comprises: a) microcomputer means having an input and an output, said microcomputer means receiving said programming message signal on said input for storing said unique identifying address therein, and said microcomputer means providing a signal at said output containing said unique identifying address; and b) address modulator means having an input connected to said microcomputer output and having an output connected to said branch cable, said address modulator means being responsive to an actuation signal on said branch cable from said programmer-reader for converting the output signal from said microcomputer means into a signal suitable for transmission on said branch cable to said programmer-reader.

8. The cable identification system according to claim 7, wherein each of said cable-identifiers further comprises power converter means connected to said branch cable and to said address modulator means for providing electrical power for operating said cable identifier in response to said activation signal.

9. The cable identification system according to claim 1, wherein said programmer-reader comprises: a) keyboard means for converting user input commands into signals at the output thereof containing information for programming the cable identifiers during said first mode and for reading the cable identifiers during said second mode; b) readout means for providing output information as to the unique identifying address read from a cable identifier during said second mode and as to the unique identifying address for programming into a cable identifier during said first mode; c) actuation signal ^'generating means having an input and having an output adapted for connection to a selected branch cable; d) address demodulator means having an output and having an input adapted for connection to a selected branch cable; and e) microcomputer means having a first input converted to the output of said keypad means for receiving signal information containing said user input commands, a second input connected to the output of said address demodulator means for receiving signals containing addresses read from said cable identifiers during said second mode, a first output connected to said readout means for determining the

ET information provided by said readout means during said first and second modes, a second output connected to said actuation signal generating means for controlling operation of said signal generating means in response to a command from said keypad means, and a third output for providing a programming message signal during said first mode in response to a command from said keypad means; and f) means for connecting said third output of said microcomputer means to a selected one of said cable identifiers.

10. The cable identification system according to claim 9, wherein said readout means comprises visual display means.

11. A cable identification device for use with a cable communication installation for multiple reception units including communications receivers in said reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a signal source or destination and including programmable and readable identification means associated with each of said reception units and operatively connected to corresponding ones of said branch cables for storing a programmed unique identifying address and transmitting said address on said branch cable when interrogated, said device comprising: a) computer means having an input adapted to be connected to any selected branch cable for receiving a signal containing the unique identifying address from the identification means asssociated with the selected branch cable in response to an activation signal, a first output for providing address information associated with the identification means, and a second output for providing a programming message signal for supplying a unique identifying address for any selected identification

UTE SHEET means; b) readout means connected to said first output of said computer means for providing information as to the address read from a selected identification means and to the address programmed into a selected identification means; and c) means for connecting said second output of said computer means to any selected identification means for applying the programming message signal thereto.

12. The cable identification device according to claim 11, further including input means operatively associated with said computer means for providing user input commands for programming addresses into selected identification means and reading addresses from selected branch cables.

13. The cable identification device according to claim 11, wherein said readout means comprises visual display means.

14. The cable identification device according to claim 11, contained in a housing which is small in size and light in weight so as to be hand-held and portable.

15. An electronic cable identification device for connection in each branch cable of a cable communication installation for multiple reception units including communications receivers in said reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a signal source or destination, said device comprising: a) a first terminal; b) a second terminal for connection to the portion of said branch cable leading to said distribution unit; c) a third terminal for connection to the portion of said branch cable leading to said reception unit; and

SUBSTITUTE SHEET d) means connected to said first and second terminals for receiving a programming message signal applied to said first terminal containing a unique identifying address, for storing said unique identifying address, and for transmitting a signal containing second unique identifying address from said second terminal along said branch cable toward said distribution unit in response to an activation signal applied to said second terminal; e) so that said unique identifying address can be read at a location remote from the reception unit such as on the end of said branch cable at said central distribution unit.

16. The electronic cable identification device according to claim 15, further including circuit means connected to said second and third terminals for preventing interference by said device with signals transmitted on said branch cable to said communication receiver.

17. A cable identification method for cable communication installation for multiple reception units including communications receivers in said reception units each connected by one of a plurality of branch cables joined at a central distribution unit to a signal source or destination, said method comprising the steps of: a) providing an electronic programmable-readable cable identifier in each of a plurality of said branch cables; b) programming a unique identifying address into a selected identifier; c) subsequently reading said address by applying an actuation signal to the branch cable containing said identifier and receiving a signal from said identifier containing said address.

18. The method according to claim 17, further including programming a plurality of unique identifying addresses into a corresponding plurality of identifiers and subsequently reading said addresses.

19. The method of claim 17, further including providing a visual indication of said address when read from the identifier.

20. The method of claim 17, further including providing a visual indication of said address when programmed into the identifier.

21. The method of claim 17, when said identifier is provided in said branch cable at a location on said branch cable adjacent the corresponding reception unit.

22. The method of claim 17, wherein said address is read at a location on said branch cable adjacent said distribution unit.