FR2292994A1 - Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of sound - Google Patents
Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of soundInfo
- Publication number
- FR2292994A1 FR2292994A1 FR7438656A FR7438656A FR2292994A1 FR 2292994 A1 FR2292994 A1 FR 2292994A1 FR 7438656 A FR7438656 A FR 7438656A FR 7438656 A FR7438656 A FR 7438656A FR 2292994 A1 FR2292994 A1 FR 2292994A1
- Authority
- FR
- France
- Prior art keywords
- sound
- slide
- track
- switch
- audio
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B31/00—Associated working of cameras or projectors with sound-recording or sound-reproducing means
- G03B31/06—Associated working of cameras or projectors with sound-recording or sound-reproducing means in which sound track is associated with successively-shown still pictures
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Signal Processing Not Specific To The Method Of Recording And Reproducing (AREA)
Abstract
The synchronisation of a slide projector with a sound track in an audio-visual message is achieved by changing slides whenever there is a sufficiently long pause in the sound track. An amplifier is connected to the signal from the sound track, and operates an electronic switch. In the absence of a sound signal the switch is open, allowing a capacitor to discharge. Unless the switch is closed by a sound level, hence re-charging the capacitor, the potential of the capacitor will fall low enough to trigger a mono-stable. This in turn operates a relay which commands the slide-projector. After a slide-change the switch is kept closed until the sound trck starts again, so that a long pause will not cause several slide changes.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7438656A FR2292994A1 (en) | 1974-11-26 | 1974-11-26 | Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of sound |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7438656A FR2292994A1 (en) | 1974-11-26 | 1974-11-26 | Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of sound |
Publications (2)
Publication Number | Publication Date |
---|---|
FR2292994A1 true FR2292994A1 (en) | 1976-06-25 |
FR2292994B3 FR2292994B3 (en) | 1977-08-26 |
Family
ID=9145232
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FR7438656A Granted FR2292994A1 (en) | 1974-11-26 | 1974-11-26 | Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of sound |
Country Status (1)
Country | Link |
---|---|
FR (1) | FR2292994A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4473280A (en) * | 1981-05-22 | 1984-09-25 | Staar S. A. | Audio-visual cartridge and combined audio player and visual viewer |
-
1974
- 1974-11-26 FR FR7438656A patent/FR2292994A1/en active Granted
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4473280A (en) * | 1981-05-22 | 1984-09-25 | Staar S. A. | Audio-visual cartridge and combined audio player and visual viewer |
Also Published As
Publication number | Publication date |
---|---|
FR2292994B3 (en) | 1977-08-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
FR2292994A1 (en) | Audio-visual synchroniser for changing slides with taped commentary - uses pause in sound-track to cause slide to change, using switch open in absence of sound | |
US3177767A (en) | Electronic timed signalling device for use in a sound and picture projector | |
GB1236784A (en) | Audio-visual recording and display methods and apparatus | |
JPS5780879A (en) | Magnetic recording and reproducing device | |
US3200206A (en) | Control apparatus | |
US2346905A (en) | Sound recording | |
GB1427928A (en) | Control signal apparatus for detecting signal presence or absence | |
US3276315A (en) | Time-controlled signal actuated switch for a slide projector | |
US3622229A (en) | Sound reproducing unit start-stop control circuit | |
US3467834A (en) | Remote slide changing control system | |
US3259010A (en) | Synchronizing means for audio-visual apparatus | |
FR2295448A1 (en) | Start-up sequencer for cine projector - uses relays and time delays to isolate sound system | |
JPS5271103A (en) | Changeover device without cutoff of radiotelegraphic apparatus | |
GB776656A (en) | System of recording or reproducing frequencies within the audible range | |
NL7411217A (en) | Electronic game of skill - has generator producing synchronising, position and direction signals for moving light spot | |
GB856778A (en) | Improvements in or relating to the synchronisation of separately running sound and picture records | |
JPS5536881A (en) | Sound overlap device for sound cine camera | |
GB1113662A (en) | An apparatus for synchronising the projection of photographic transparencies with commentaries thereon recorded on a magnetic tape | |
JPS51151507A (en) | Magnetic record reproducing device | |
FR2323207A1 (en) | Tape recorder drive control system - consists of bistable circuit responsive to supplementary control signals | |
GB1285981A (en) | Control arrangement for a plurality of slide projectors | |
JPS522123A (en) | Video amplifier output circuit | |
JPS53131710A (en) | Automatic answering telephone set | |
JPS5219909A (en) | Receiver | |
JPS522528A (en) | Synchronizing device for a lide projector |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
ST | Notification of lapse |