NL70720C - - Google Patents

Info

Publication number: NL70720C
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.)

1941-09-15

Publication of NL70720C publication Critical patent/NL70720C/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
- H04Q1/446—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency
- H04Q1/4465—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using one signalling frequency the same frequency being used for all signalling information, e.g. A.C. nr.9 system

Landscapes

Engineering & Computer Science (AREA)
Computer Networks & Wireless Communication (AREA)
Amplifiers (AREA)
Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
Interface Circuits In Exchanges (AREA)

NL70720D 1941-09-15 NL70720C (en)

Applications Claiming Priority (1)

Application Number	Priority Date	Filing Date	Title
GB11782/41A GB551951A (en)	1941-09-15	1941-09-15	Improvements in or relating to electric signalling systems

Publications (1)

Publication Number	Publication Date
NL70720C true NL70720C (en)

Family

ID=27799776

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
NL70720D NL70720C (en)	1941-09-15

Country Status (6)

Country	Link
US (1)	US2343759A (en)
BE (1)	BE479786A (en)
CH (1)	CH254957A (en)
FR (1)	FR933246A (en)
GB (1)	GB551951A (en)
NL (1)	NL70720C (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US2476311A (en) *	1943-02-01	1949-07-19	Sperry Corp	Ultra high frequency discriminator and apparatus
US2533286A (en) *	1946-07-22	1950-12-12	Univ Minnesota	Heat sensitive circuits
BE481448A (en) *	1947-02-07
US2706272A (en) *	1949-11-03	1955-04-12	Jones Lloyd	Voltage stabilizing circuit
US2801290A (en) *	1951-09-17	1957-07-30	Telefunken Gmbh	Calling signal responder arrangements
US2957950A (en) *	1954-11-18	1960-10-25	Bell Telephone Labor Inc	Transistor selective ringing circuit
US2987713A (en) *	1957-07-12	1961-06-06	Kidde & Co Walter	Sensitivity control of apparatus for detecting distrubances in an enclosure

0
- NL NL70720D patent/NL70720C/xx active
- BE BE479786D patent/BE479786A/xx unknown
1941
- 1941-09-15 GB GB11782/41A patent/GB551951A/en not_active Expired
1942
- 1942-06-17 US US447394A patent/US2343759A/en not_active Expired - Lifetime
1946
- 1946-05-24 CH CH254957D patent/CH254957A/en unknown
- 1946-09-04 FR FR933246D patent/FR933246A/en not_active Expired

Also Published As

Publication number	Publication date
BE479786A (en)
US2343759A (en)	1944-03-07
GB551951A (en)	1943-03-17
FR933246A (en)	1948-04-14
CH254957A (en)	1948-05-31

Publication	Publication Date	Title
FR959681A (en)	1950-03-31
BE442109A (en)	1941-08-30
BE442867A (en)
BE442850A (en)
BE441196A (en)
BE441261A (en)
NL70720C (en)
BE444893A (en)
BE441273A (en)
BE441477A (en)	1941-06-30
BE441524A (en)
BE441571A (en)	1941-06-30
BE441636A (en)
BE441671A (en)
BE441713A (en)	1941-07-31
BE441833A (en)
BE441893A (en)
SE108997C1 (en)	1943-11-09
NL81679C (en)
NL71321C (en)
NL59539C (en)
BE442102A (en)
NL59080C (en)
BE442130A (en)
BE442153A (en)