BE401688A - - Google Patents
Info
- Publication number
- BE401688A BE401688A BE401688DA BE401688A BE 401688 A BE401688 A BE 401688A BE 401688D A BE401688D A BE 401688DA BE 401688 A BE401688 A BE 401688A
- Authority
- BE
- Belgium
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
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/12—Sanitary or hygienic devices for mouthpieces or earpieces, e.g. for protecting against infection
Landscapes
- Health & Medical Sciences (AREA)
- Public Health (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Telephone Set Structure (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PT417431X | 1934-02-01 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| BE401688A true BE401688A (pl) |
Family
ID=20081617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| BE401688D BE401688A (pl) | 1934-02-01 |
Country Status (3)
| Country | Link |
|---|---|
| BE (1) | BE401688A (pl) |
| FR (1) | FR769416A (pl) |
| GB (1) | GB417431A (pl) |
-
0
- BE BE401688D patent/BE401688A/xx unknown
-
1934
- 1934-02-28 FR FR769416D patent/FR769416A/fr not_active Expired
- 1934-03-19 GB GB8600/34A patent/GB417431A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| FR769416A (fr) | 1934-08-25 |
| GB417431A (en) | 1934-10-04 |