GB993585A
(en )
1965-05-26
Repeater for multiplex communication system
US2924703A
(en )
1960-02-09
Communication control system
GB1026212A
(en )
1966-04-14
Frequency modulated communication system with improved signal to noise ratio
US3045066A
(en )
1962-07-17
Selective carrier type communication system
US2613279A
(en )
1952-10-07
Ringing and regulating device for carrier current transmission systems
GB1521651A
(en )
1978-08-16
Transceiver including audio compressor system
GB1220866A
(en )
1971-01-27
Improvements in or relating to intelligence communication systems
US2480115A
(en )
1949-08-30
Radio control system
GB1234074A
(GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html )
1971-06-03
GB1019410A
(en )
1966-02-09
Voice frequency signalling system
US4011530A
(en )
1977-03-08
Two-path telephone line equalization system
GB1499725A
(en )
1978-02-01
Electronic time switching telephone systems
US3321581A
(en )
1967-05-23
Voice operated gain adjusting device
HK48487A
(en )
1987-07-03
Automatic kinescope beam current limiter
GB910772A
(en )
1962-11-21
Improvements in continuous tone-controlled squelch system
US4081609A
(en )
1978-03-28
Synchronous ring detector for station carrier telephone systems
GB731680A
(en )
1955-06-15
Improvements in or relating to devices for automatic level regulation in multi-channel carrier frequency line transmission systems
GB942230A
(en )
1963-11-20
Control arrangement for carrier frequency operated television and similar systems
GB1078947A
(en )
1967-08-09
Improvements in or relating to communication systems
GB1226069A
(GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html )
1971-03-24
US3958082A
(en )
1976-05-18
Circuit arrangement for controlling of amplification devices in a semi-duplex data signal transmission system
US3496308A
(en )
1970-02-17
Level control for subscriber carrier system
US3328695A
(en )
1967-06-27
Receiver muting system for two-way radio communication equipment
JPS5735457A
(en )
1982-02-26
Loudspeaker telephone set system
US3617888A
(en )
1971-11-02
Encoder-decoder device for selective signalling