NL54870C - - Google Patents

Info

Publication number: NL54870C
Authority: NL; Netherlands

Application number

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.)

1938-07-30

Publication of NL54870C publication Critical patent/NL54870C/xx

Classifications

- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q1/00—Details of selecting apparatus or arrangements
- H04Q1/18—Electrical details
- H04Q1/30—Signalling arrangements; Manipulation of signalling currents
- H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
- H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
- H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
- H04L27/12—Modulator circuits; Transmitter circuits
- 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

Landscapes

Engineering & Computer Science (AREA)
Computer Networks & Wireless Communication (AREA)
Signal Processing (AREA)
Relay Circuits (AREA)
Transmitters (AREA)

NL54870D 1938-07-30 NL54870C (th)

Applications Claiming Priority (1)

Application Number	Priority Date	Filing Date	Title
DEL95315D DE724392C (de)	1938-07-30	1938-07-30	Schaltungsanordnung zur Erzeugung von zwei im Takt einer dritten Frequenz abwechselnden Tonfrequenzen fuer die Tonfrequenzwahl in Fernsprechanlagen

Publications (1)

Publication Number	Publication Date
NL54870C true NL54870C (th)

Family

ID=7288086

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
NL54870D NL54870C (th)	1938-07-30

Country Status (6)

Country	Link
US (1)	US2285088A (th)
BE (1)	BE435699A (th)
CH (1)	CH212069A (th)
DE (1)	DE724392C (th)
FR (1)	FR858470A (th)
NL (1)	NL54870C (th)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US2510531A (en) *	1947-10-31	1950-06-06	Rca Corp	Transmitter monitor

0
- BE BE435699D patent/BE435699A/xx unknown
- NL NL54870D patent/NL54870C/xx active
1938
- 1938-07-30 DE DEL95315D patent/DE724392C/de not_active Expired
1939
- 1939-07-24 FR FR858470D patent/FR858470A/fr not_active Expired
- 1939-07-26 CH CH212069D patent/CH212069A/de unknown
- 1939-07-29 US US287197A patent/US2285088A/en not_active Expired - Lifetime

Also Published As

Publication number	Publication date
US2285088A (en)	1942-06-02
CH212069A (de)	1940-10-31
BE435699A (th)
FR858470A (fr)	1940-11-26
DE724392C (de)	1942-08-25

Publication	Publication Date	Title
BE425826A (th)	1938-02-28
BE426920A (th)	1938-04-30
BE432464A (th)
BE428127A (th)
BE426318A (th)
BE427383A (th)	1938-06-30
BE428011A (th)
BE427511A (th)
BE414985A (th)
BE423383A (th)
BE441131A (th)
BE428063A (th)	1938-06-30
NL55649C (th)	1943-12-15
BE427269A (th)
BE435699A (th)
BE428344A (th)
NL51033C (th)
NL49939C (th)
NL53295C (th)
BE427768A (th)	1938-05-31
BE427924A (th)
BE426985A (th)
BE427877A (th)	1938-06-30
BE427957A (th)
BE426748A (th)