FRIEDRICH MERK TELEFONBAU AKT innovation strategy

Patent filings in countries

#	Industry
#1	Telecommunications
#2	Machines
#3	Electrical machinery and energy

#	Technology
#1	Telephonic communication
#2	Unspecified technologies
#3	Electrically-conductive connections
#4	Selecting

Publication	Filing date	Title
DE803357C	1949-06-02	Circuit arrangement for telephone systems with a main and a branch
DE803245C	1948-10-02	Circuit arrangement for branches with a main line to the office and two branch lines in automatic telephone systems
DE802395C	1948-10-02	Circuit arrangement for the connection of two-wire and four-wire lines in exchanges
DE803244C	1948-10-02	Circuit arrangement for extension switch in telephone systems
DE803246C	1948-10-02	Circuit arrangement for the distribution of calls to workplaces of telephone systems
DE802697C	1948-10-02	Circuit arrangement for the conversation counting in manually operated extension switches in automatic telephone systems
GB459375A	1935-08-10	Improvements in and relating to metering systems in telephone installations
DE677482C	1934-04-01	Circuit arrangement for time or time and zone counting devices
DE635669C	1932-11-02	Device for determining the number of a calling subscriber in self-access connection systems
DE671104C	1932-09-04	Device for time and zone counting
DE684065C	1932-09-04	Device for determining the value corresponding to any dialer setting in telecommunications systems
DE666173C	1931-04-29	Time zone counter for telecommunications systems with dialer operation
DE492257C	1926-12-19	Circuit arrangement for telephone exchanges with dialer operation
DE501009C	1926-11-28	Device for connecting telephone stations to the supply line