FR958867A - - Google Patents
Info
- Publication number
- FR958867A FR958867A FR958867DA FR958867A FR 958867 A FR958867 A FR 958867A FR 958867D A FR958867D A FR 958867DA FR 958867 A FR958867 A FR 958867A
- Authority
- FR
- France
- Legal status (The legal status 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 status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M3/00—Automatic or semi-automatic exchanges
- H04M3/40—Applications of speech amplifiers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F13/00—Amplifiers using amplifying element consisting of two mechanically- or acoustically-coupled transducers, e.g. telephone-microphone amplifier
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
- H03F3/62—Two-way amplifiers
- H03F3/64—Two-way amplifiers with tubes only
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Signal Processing (AREA)
- Amplifiers (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR2454812X | 1940-03-23 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| FR958867A true FR958867A (en) | 1950-03-21 |
Family
ID=9685490
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR958867D Expired FR958867A (en) | 1940-03-23 |
Country Status (2)
| Country | Link |
|---|---|
| US (1) | US2454812A (en) |
| FR (1) | FR958867A (en) |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1622507A (en) * | 1927-03-29 | Vibration amplifier | ||
| US1306248A (en) * | 1919-06-10 | Bis sfczct | ||
| US814411A (en) * | 1905-07-14 | 1906-03-06 | John Trowbridge | Telephonic relay. |
| US975933A (en) * | 1910-03-03 | 1910-11-15 | Samuel L Campbell | Telephone-repeater. |
| US1088923A (en) * | 1913-03-31 | 1914-03-03 | Long Distance Telephone Equipment Co | Electrical sound-transmitter. |
| US1683946A (en) * | 1926-06-14 | 1928-09-11 | Baldwin Nathaniel | Loud speaker |
| US1952577A (en) * | 1931-02-27 | 1934-03-27 | Bell Telephone Labor Inc | Mechanical amplifier |
| US2105296A (en) * | 1934-10-04 | 1938-01-11 | Sonotone Corp | Hearing aid |
| US2080837A (en) * | 1935-04-02 | 1937-05-18 | Rca Corp | Tube base |
| US2137424A (en) * | 1936-10-20 | 1938-11-22 | Rca Corp | Electron tube |
| US2257840A (en) * | 1940-03-15 | 1941-10-07 | Dubilier William | Hearing aid amplifier |
-
0
- FR FR958867D patent/FR958867A/fr not_active Expired
-
1943
- 1943-11-29 US US512123A patent/US2454812A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| US2454812A (en) | 1948-11-30 |