GB519727A - Improvement in television receivers - Google Patents
Improvement in television receiversInfo
- Publication number
- GB519727A GB519727A GB28169/38A GB2816938A GB519727A GB 519727 A GB519727 A GB 519727A GB 28169/38 A GB28169/38 A GB 28169/38A GB 2816938 A GB2816938 A GB 2816938A GB 519727 A GB519727 A GB 519727A
- Authority
- GB
- United Kingdom
- Prior art keywords
- circuit
- signals
- vision
- local oscillator
- sound
- 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.)
- Expired
Links
- 230000008878 coupling Effects 0.000 abstract 3
- 238000010168 coupling process Methods 0.000 abstract 3
- 238000005859 coupling reaction Methods 0.000 abstract 3
- 230000005236 sound signal Effects 0.000 abstract 3
- 239000004020 conductor Substances 0.000 abstract 2
- 230000005540 biological transmission Effects 0.000 abstract 1
- 230000000903 blocking effect Effects 0.000 abstract 1
- 230000002452 interceptive effect Effects 0.000 abstract 1
- 230000007935 neutral effect Effects 0.000 abstract 1
- 230000010355 oscillation Effects 0.000 abstract 1
- 230000011664 signaling Effects 0.000 abstract 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N5/00—Details of television systems
- H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
- H04N5/60—Receiver circuitry for the reception of television signals according to analogue transmission standards for the sound signals
Landscapes
- Engineering & Computer Science (AREA)
- Multimedia (AREA)
- Signal Processing (AREA)
- Television Receiver Circuits (AREA)
- Superheterodyne Receivers (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
519,727. Multiplex wireless signalling. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. Sept. 28, 1938, No. 28169. Convention date, Sept. 29,1937. [Classes 40 (iii) and 40 (v)] In a superheterodyne television receiver for the reception of associated picture and sound signals, in which the sound I.F. signals are transferred to a superheterodyne broadcast receiver, a trap circuit is employed to prevent the local oscillator of the broadcast receiver interfering with the vision I.F. signals. The input signals are supplied from the aerial via the tunable circuits 12 which have a wide pass range to the first detector 10, which is also fed by the local oscillator 22. The vision I.F. amplifier 11 is connected to the first detector over a band pass coupling circuit consisting of tuned primary and secondary circuits with a coupling coil 28. The primary circuit consists of adjustable inductance 26 and the valve and distributed capacity 36. Similarly, the secondary circuit which is connected through the blocking condenser 25 consists of the adjustable inductance 27 and the valve input capacity 37. The primary and secondary circuits are so coupled and tuned as to pass the band of picture signals and to reject the sound signals. The broadcast receiver 24 is supplied with sound signals by a conductor 41 leading from the high potential end of coil 28 through a parallel resonant circuit 42, 43 and a condenser 44 which tunes the whole circuit to be series resonant to the sound I.F. The parallel circuit 42, 43 is tuned to the local oscillator frequency of the receiver 24 and voltage from this local oscillator, whose frequency falls within the vision I.F. band, is thus prevented from reaching the amplifier 11. Switches 51, 56, and conductor 53 are provided to enable the broadcast receiver to be disconnected from the band pass coupling and connected to the mid-point of the input coil 16, thus utilising the television antenna and transmission line for normal broadcast reception. The switches 51, 56 are preferably ganged with the television receiver power switch. The first detector valve 10 is of the pentode type and has the screen and suppressor grids connected together to increase the neutral conductance. For the same reason the vision I.F. amplifier has its screen and suppressor electrodes connected, but a resistor 38 is included to prevent oscillation.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US166287A US2240295A (en) | 1937-09-29 | 1937-09-29 | Television receiver |
Publications (1)
Publication Number | Publication Date |
---|---|
GB519727A true GB519727A (en) | 1940-04-04 |
Family
ID=22602621
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB28169/38A Expired GB519727A (en) | 1937-09-29 | 1938-09-28 | Improvement in television receivers |
Country Status (4)
Country | Link |
---|---|
US (1) | US2240295A (en) |
CH (1) | CH208107A (en) |
FR (1) | FR843471A (en) |
GB (1) | GB519727A (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2624838A (en) * | 1945-12-07 | 1953-01-06 | Int Standard Electric Corp | Radio receiver employing band pass coupling circuit arrangements |
US2581159A (en) * | 1948-05-28 | 1952-01-01 | Rca Corp | Tunable band pass amplifier for television |
US2619536A (en) * | 1948-12-09 | 1952-11-25 | Zenith Radio Corp | Electrical signal network |
BE504576A (en) * | 1950-07-12 | |||
DE967209C (en) * | 1951-10-13 | 1957-10-24 | Interessengemeinschaft Fuer Ru | Combined receiver for radio and television broadcasts |
-
1937
- 1937-09-29 US US166287A patent/US2240295A/en not_active Expired - Lifetime
-
1938
- 1938-09-14 FR FR843471D patent/FR843471A/en not_active Expired
- 1938-09-27 CH CH208107D patent/CH208107A/en unknown
- 1938-09-28 GB GB28169/38A patent/GB519727A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
CH208107A (en) | 1939-12-31 |
FR843471A (en) | 1939-07-04 |
US2240295A (en) | 1941-04-29 |
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