NL187779B
(en )
AUDIO AMPLIFIER.
DK105927C
(en )
1966-11-28
Sound reproduction system.
NL142044B
(en )
1974-04-16
ELECTRODYNAMIC SPEAKER.
CH245420A
(en )
1946-11-15
Electrodynamic speaker.
DK73887C
(en )
1952-03-17
Vibration system, in particular electrodynamic vibration system, eg for microphones and loudspeakers.
FR909299A
(en )
1946-05-03
Sound system by loudspeaker, in particular t station. s. f., amplifier, loudspeaker, etc.
CH270139A
(en )
1950-08-15
Pressure telegraph receiver.
NL184037B
(en )
SPEAKER SYSTEM.
DK70808C
(en )
1950-04-03
Electrodynamic microphone.
DK72732C
(en )
1951-07-09
Electroacoustic apparatus, eg a microphone.
FR1086050A
(en )
1955-02-09
Advanced electrodynamic speaker
CH245733A
(en )
1946-11-30
Electrodynamic phonogram scanner.
CH275629A
(en )
1951-05-31
Pressure telegraph receiver.
FR928854A
(en )
1947-12-10
Improvements to electrodynamic speakers or microphones
CH264765A
(en )
1949-10-31
Microphone.
ES171459A1
(en )
1945-12-01
IMPROVEMENTS IN FACSIMILE TELEGRAPH SYSTEMS AND APPARATUS.
DK72080C
(en )
1951-01-29
Electrodynamic device, eg pick-up.
DK94519C
(en )
1962-10-15
Electrodynamic device, in particular microphone or loudspeaker.
FR950341A
(en )
1949-09-23
Secret communication system
DK77109C
(en )
1954-02-15
Stand, eg music stand or microphone stand.
ES12184Y
(en )
1946-04-16
Improvements in forms for secret telegraphic reception.
DK112347B
(en )
1968-12-02
Electrodynamic sound repeater.
ES176498A1
(en )
1947-03-01
IMPROVEMENTS INTRODUCED IN VIBRANT MEMBRANES INTENDED ESPECIALLY FOR MICROPHONES, SPEAKERS AND IN GENERAL FOR ELECTROACOUSTIC APPLIANCES
CH309043A
(en )
1955-08-15
Teletype receiver.
ES15164Y
(en )
1947-11-16
Trunk-conical membranes for speakers.