ES403458A1 - Circuito de bloqueo a la teleseleccion y a los servicios tasados en general para aparatos telefonicos de usuario. - Google Patents
Circuito de bloqueo a la teleseleccion y a los servicios tasados en general para aparatos telefonicos de usuario.Info
- Publication number
- ES403458A1 ES403458A1 ES403458A ES403458A ES403458A1 ES 403458 A1 ES403458 A1 ES 403458A1 ES 403458 A ES403458 A ES 403458A ES 403458 A ES403458 A ES 403458A ES 403458 A1 ES403458 A1 ES 403458A1
- Authority
- ES
- Spain
- Prior art keywords
- flop
- digit
- flip
- dialing
- central office
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/66—Substation equipment, e.g. for use by subscribers with means for preventing unauthorised or fraudulent calling
- H04M1/677—Preventing the dialling or sending of predetermined telephone numbers or selected types of telephone numbers, e.g. long distance numbers
Landscapes
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Signal Processing (AREA)
- Telephonic Communication Services (AREA)
- Interface Circuits In Exchanges (AREA)
- Prepayment Telephone Systems (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT3258471A IT944106B (it) | 1970-12-17 | 1971-12-17 | Procedimento per la preparazione di esteri acrilato e metacrilato da composti organici insaturi |
Publications (1)
Publication Number | Publication Date |
---|---|
ES403458A1 true ES403458A1 (es) | 1975-05-01 |
Family
ID=11235507
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
ES403458A Expired ES403458A1 (es) | 1971-12-17 | 1972-05-20 | Circuito de bloqueo a la teleseleccion y a los servicios tasados en general para aparatos telefonicos de usuario. |
Country Status (4)
Country | Link |
---|---|
US (1) | US3899640A (es) |
DE (1) | DE2261906C3 (es) |
ES (1) | ES403458A1 (es) |
GB (1) | GB1371120A (es) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4177358A (en) * | 1974-09-16 | 1979-12-04 | Mason John W | Tone dial toll restrictor |
US4012602A (en) * | 1975-03-14 | 1977-03-15 | Litton Business Telephone Systems, Inc. | Toll restrictor for touch type digit selector |
US3980836A (en) * | 1975-05-05 | 1976-09-14 | International Components Corporation | Toll restricting method and apparatus |
US4092500A (en) * | 1976-08-30 | 1978-05-30 | Hughes George W | Device for selectively interrupting mechanical operation of a manually operated telephone |
JPS5383402A (en) * | 1976-12-28 | 1978-07-22 | Tamura Electric Works Ltd | Dial number control system |
US4124781A (en) * | 1977-08-31 | 1978-11-07 | Akzona Incorporated | Telephone toll restrictor |
US4209668A (en) * | 1978-09-20 | 1980-06-24 | Utility Verification Corp. | Telephone having reiterative dialing feature |
US4251692A (en) * | 1978-10-06 | 1981-02-17 | Waldman Herbert H | Telephone call restricting apparatus |
US6700963B1 (en) | 1998-04-08 | 2004-03-02 | Worldcom, Inc. | System and method therefor of preventing fraud on pay phone credit/debit calling card authorization |
CA2279684C (en) * | 1999-08-05 | 2007-05-15 | Vtech Communications, Ltd. | Method and apparatus for telephone call fraud detection and prevention |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3651275A (en) * | 1969-11-24 | 1972-03-21 | Bell Telephone Labor Inc | Toll diverting circuit |
CH537677A (it) * | 1970-10-06 | 1973-05-31 | It Telecommunicazioni Siemens | Dispositivo di blocco alla teleselezione e ai servizi tassati in generale per apparecchi telefonici d'utente |
US3748396A (en) * | 1971-04-14 | 1973-07-24 | Itt | Direct inward dialing trunk circuit |
-
1972
- 1972-05-20 ES ES403458A patent/ES403458A1/es not_active Expired
- 1972-10-16 GB GB4754072A patent/GB1371120A/en not_active Expired
- 1972-12-18 US US315892A patent/US3899640A/en not_active Expired - Lifetime
- 1972-12-18 DE DE2261906A patent/DE2261906C3/de not_active Expired
Also Published As
Publication number | Publication date |
---|---|
DE2261906C3 (de) | 1981-11-26 |
US3899640A (en) | 1975-08-12 |
GB1371120A (en) | 1974-10-23 |
DE2261906A1 (de) | 1973-07-05 |
DE2261906B2 (de) | 1981-02-19 |
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