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.)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tamura Electric Works Ltd
Original Assignee
Tamura Electric Works Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from JP6239474Uexternal-prioritypatent/JPS5324167Y2/ja
Priority claimed from JP7373074Uexternal-prioritypatent/JPS512114U/ja
Priority claimed from JP7421174Uexternal-prioritypatent/JPS514205U/ja
Application filed by Tamura Electric Works LtdfiledCriticalTamura Electric Works Ltd
Publication of FR2275948A1publicationCriticalpatent/FR2275948A1/fr
Application grantedgrantedCritical
Publication of FR2275948B1publicationCriticalpatent/FR2275948B1/fr
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
Landscapes
Engineering & Computer Science
(AREA)
Signal Processing
(AREA)
Devices For Supply Of Signal Current
(AREA)
FR7516846A1974-05-301975-05-29Appareils de telephone a sonneries interchangeables
GrantedFR2275948A1
(fr)