NL57470C - - Google Patents
Info
- Publication number
- NL57470C NL57470C NL87181A NL87181A NL57470C NL 57470 C NL57470 C NL 57470C NL 87181 A NL87181 A NL 87181A NL 87181 A NL87181 A NL 87181A NL 57470 C NL57470 C NL 57470C
- Authority
- NL
- Netherlands
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R21/00—Variable-resistance transducers
- H04R21/02—Microphones
- H04R21/021—Microphones with granular resistance material
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Diaphragms And Bellows (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US134044A US2191992A (en) | 1937-03-31 | 1937-03-31 | Telephone transmitter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NL57470C true NL57470C (fr) | 1946-05-15 |
Family
ID=22461499
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NL87181A NL57470C (fr) | 1937-03-31 | 1938-03-31 |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US2191992A (fr) |
| BE (1) | BE427273A (fr) |
| FR (1) | FR835932A (fr) |
| NL (1) | NL57470C (fr) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE482597A (fr) * | 1944-08-15 | |||
| US2481771A (en) * | 1945-08-25 | 1949-09-13 | Bendix Aviat Corp | Carbon pile regulator |
| US2482972A (en) * | 1945-09-10 | 1949-09-27 | Bendix Aviat Corp | Electron tube type phonograph reproducer |
| US2481782A (en) * | 1945-09-26 | 1949-09-13 | Bendix Aviat Corp | Carbon pile regulator |
| US2481752A (en) * | 1946-05-15 | 1949-09-13 | Bendix Aviat Corp | Electric regulator with diaphragm type spring |
| NL70196C (fr) * | 1947-10-31 | |||
| US2532741A (en) * | 1947-10-31 | 1950-12-05 | Bell Telephone Labor Inc | Microphone with opposite electrodes being of varying and constant curvature |
| US2562526A (en) * | 1949-12-01 | 1951-07-31 | Stromberg Carlson Co | Telephone transmitter |
| DE976947C (de) * | 1952-06-25 | 1964-09-17 | Standard Elek K Lorenz Ag | Federnde Einspannung der Membran einer Sprech- oder Hoerkapsel |
| US3020346A (en) * | 1957-12-09 | 1962-02-06 | Lionel Corp | Microphone for sound dispatching station |
-
1937
- 1937-03-31 US US134044A patent/US2191992A/en not_active Expired - Lifetime
-
1938
- 1938-03-30 FR FR835932D patent/FR835932A/fr not_active Expired
- 1938-03-31 NL NL87181A patent/NL57470C/xx active
- 1938-03-31 BE BE427273D patent/BE427273A/xx unknown
Also Published As
| Publication number | Publication date |
|---|---|
| BE427273A (fr) | 1938-04-30 |
| FR835932A (fr) | 1939-01-05 |
| US2191992A (en) | 1940-02-27 |