JPS5787657A - Loudspeaker telephone system - Google Patents
Loudspeaker telephone systemInfo
- Publication number
- JPS5787657A JPS5787657A JP16337580A JP16337580A JPS5787657A JP S5787657 A JPS5787657 A JP S5787657A JP 16337580 A JP16337580 A JP 16337580A JP 16337580 A JP16337580 A JP 16337580A JP S5787657 A JPS5787657 A JP S5787657A
- Authority
- JP
- Japan
- Prior art keywords
- call
- loudspeaker
- handset
- power failure
- circuit
- Prior art date
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
- H04M1/6033—Substation equipment, e.g. for use by subscribers including speech amplifiers for providing handsfree use or a loudspeaker mode in telephone sets
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
Abstract
PURPOSE:To avoid disabled communication due to mis-operation and to hold the telephone line even at power failure, by automatically restoring a loudspeaker switch at the end of call. CONSTITUTION:When a handset 3 is disconnected, hook switches HS1, HS2 are changed over and normal telephone call can be made with a telephone set circuit 2. When a start switch in a control circuit 8 is depressed, a relay is activated, contacts S1-S3 are selected, and loudspeaker call can be made through a loudspeaker telephone circuit 5, speaker 6 and microphone 7. At the end of call, a hook switch is off-hooked once for on-hook again or another start switch can be depressed for the end of call. If power failure takes place during the loudspeaker call, an alarm takes place through the operation of power failure detection and an alarm circuit (not shown). In this case, when the handset is off- hooked, the relay is restored and the handset call is obtained.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16337580A JPS5787657A (en) | 1980-11-21 | 1980-11-21 | Loudspeaker telephone system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP16337580A JPS5787657A (en) | 1980-11-21 | 1980-11-21 | Loudspeaker telephone system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5787657A true JPS5787657A (en) | 1982-06-01 |
Family
ID=15772681
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP16337580A Pending JPS5787657A (en) | 1980-11-21 | 1980-11-21 | Loudspeaker telephone system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5787657A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61208951A (en) * | 1985-03-13 | 1986-09-17 | Sharp Corp | Loudspeaker telephone set |
US11395575B2 (en) | 2016-10-31 | 2022-07-26 | Flint Group IP Holdings Limited | Lint removing device |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5012910A (en) * | 1973-04-05 | 1975-02-10 |
-
1980
- 1980-11-21 JP JP16337580A patent/JPS5787657A/en active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5012910A (en) * | 1973-04-05 | 1975-02-10 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS61208951A (en) * | 1985-03-13 | 1986-09-17 | Sharp Corp | Loudspeaker telephone set |
JPH0444860B2 (en) * | 1985-03-13 | 1992-07-23 | Sharp Kk | |
US11395575B2 (en) | 2016-10-31 | 2022-07-26 | Flint Group IP Holdings Limited | Lint removing device |
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