NL13467C - - Google Patents
Info
- Publication number
- NL13467C NL13467C NL13467DA NL13467C NL 13467 C NL13467 C NL 13467C NL 13467D A NL13467D A NL 13467DA NL 13467 C NL13467 C NL 13467C
- Authority
- NL
- Netherlands
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/02—Constructional features of telephone sets
- H04M1/21—Combinations with auxiliary equipment, e.g. with clocks or memoranda pads
- H04M1/215—Combinations with auxiliary equipment, e.g. with clocks or memoranda pads by non-intrusive coupling means, e.g. acoustic couplers
- H04M1/2155—Acoustic coupling
-
- 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
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
- H04R1/34—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means
- H04R1/345—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by using a single transducer with sound reflecting, diffracting, directing or guiding means for loudspeakers
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Telephone Set Structure (AREA)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK202268X | 1922-08-08 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NL13467C true NL13467C (en) |
Family
ID=8149913
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NL13467D NL13467C (en) | 1922-08-08 |
Country Status (4)
| Country | Link |
|---|---|
| DE (1) | DE387900C (en) |
| FR (1) | FR562185A (en) |
| GB (1) | GB202268A (en) |
| NL (1) | NL13467C (en) |
-
0
- NL NL13467D patent/NL13467C/xx active
-
1922
- 1922-11-19 DE DEA38832D patent/DE387900C/en not_active Expired
-
1923
- 1923-02-03 GB GB3262/23A patent/GB202268A/en not_active Expired
- 1923-02-15 FR FR562185D patent/FR562185A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE387900C (en) | 1924-01-09 |
| GB202268A (en) | 1923-10-18 |
| FR562185A (en) | 1923-11-05 |