JPS5054206A - - Google Patents
Info
- Publication number
- JPS5054206A JPS5054206A JP49072420A JP7242074A JPS5054206A JP S5054206 A JPS5054206 A JP S5054206A JP 49072420 A JP49072420 A JP 49072420A JP 7242074 A JP7242074 A JP 7242074A JP S5054206 A JPS5054206 A JP S5054206A
- Authority
- JP
- Japan
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
- H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
- H04M19/04—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone the ringing-current being generated at the substations
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M11/00—Telephonic communication systems specially adapted for combination with other electrical systems
- H04M11/02—Telephonic communication systems specially adapted for combination with other electrical systems with bell or annunciator systems
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M9/00—Arrangements for interconnection not involving centralised switching
- H04M9/001—Two-way communication systems between a limited number of parties
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Devices For Supply Of Signal Current (AREA)
- Telephonic Communication Services (AREA)
- Interconnected Communication Systems, Intercoms, And Interphones (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA174,906A CA998484A (en) | 1973-06-26 | 1973-06-26 | Audio frequency signalling systems for telephone systems |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5054206A true JPS5054206A (ja) | 1975-05-13 |
Family
ID=4097099
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP49072420A Pending JPS5054206A (ja) | 1973-06-26 | 1974-06-26 |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US3894197A (ja) |
| JP (1) | JPS5054206A (ja) |
| CA (1) | CA998484A (ja) |
| DE (1) | DE2430713A1 (ja) |
| FR (1) | FR2235557B3 (ja) |
| GB (1) | GB1465534A (ja) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4185173A (en) * | 1976-10-01 | 1980-01-22 | Nippon Tsu Shin Kogyo K.K. | Key telephone call signalling circuit |
| US4219699A (en) * | 1978-10-13 | 1980-08-26 | Wescom, Inc. | Telephone supervision system using DTMF signals |
| US4313038A (en) * | 1978-10-13 | 1982-01-26 | Wescom, Inc. | DTMF Signal receiver |
| US4262171A (en) * | 1979-01-08 | 1981-04-14 | Catalyst Research Corporation | Telephone system in which communication between stations is controlled by computers at each individual station |
| CA1169597A (en) * | 1981-09-11 | 1984-06-19 | Gordon D. Benning | Home communications and control system |
| FR2524743A1 (fr) * | 1982-04-01 | 1983-10-07 | Wadel Alain | Systeme d'alerte entre un centre de secours et des abonnes telephoniques a travers des lignes telephoniques |
| US4650489A (en) * | 1986-01-30 | 1987-03-17 | Massachusetts Institute Of Technology | Prosthetic device for implantation in bone |
| DE3606516C1 (de) * | 1986-02-28 | 1987-06-19 | Telefonbau & Normalzeit Gmbh | Schaltungsanordnung fuer Freisprech- und Lauthoereinrichtungen bei Fernsprechapparaten |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3459895A (en) * | 1966-05-19 | 1969-08-05 | Itt | Centrally powered subscriber carrier systems |
| US3601538A (en) * | 1969-02-24 | 1971-08-24 | Stromberg Carlson Corp | Carrier and voice-frequency telephone system |
| US3781481A (en) * | 1971-09-30 | 1973-12-25 | Stromberg Carlson Corp | Amplifier select and control circuit |
| CA968477A (en) * | 1972-07-24 | 1975-05-27 | Microsystems International Limited | Threshold circuit for tone-ringer or like load means |
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1973
- 1973-06-26 CA CA174,906A patent/CA998484A/en not_active Expired
- 1973-07-09 US US377831A patent/US3894197A/en not_active Expired - Lifetime
-
1974
- 1974-05-09 GB GB2048074A patent/GB1465534A/en not_active Expired
- 1974-06-19 FR FR7421276A patent/FR2235557B3/fr not_active Expired
- 1974-06-26 JP JP49072420A patent/JPS5054206A/ja active Pending
- 1974-06-26 DE DE2430713A patent/DE2430713A1/de active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| FR2235557A1 (ja) | 1975-01-24 |
| US3894197A (en) | 1975-07-08 |
| FR2235557B3 (ja) | 1977-04-15 |
| GB1465534A (en) | 1977-02-23 |
| DE2430713A1 (de) | 1975-01-23 |
| CA998484A (en) | 1976-10-12 |