GB1025709A - Resistance-capacitance type oscillators and selective amplifiers - Google Patents
Resistance-capacitance type oscillators and selective amplifiersInfo
- Publication number
- GB1025709A GB1025709A GB5132/63A GB513263A GB1025709A GB 1025709 A GB1025709 A GB 1025709A GB 5132/63 A GB5132/63 A GB 5132/63A GB 513263 A GB513263 A GB 513263A GB 1025709 A GB1025709 A GB 1025709A
- Authority
- GB
- United Kingdom
- Prior art keywords
- frequency
- photo
- light
- sensitive
- replaced
- 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
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B17/00—Generation of oscillations using radiation source and detector, e.g. with interposed variable obturator
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03B—GENERATION OF OSCILLATIONS, DIRECTLY OR BY FREQUENCY-CHANGING, BY CIRCUITS EMPLOYING ACTIVE ELEMENTS WHICH OPERATE IN A NON-SWITCHING MANNER; GENERATION OF NOISE BY SUCH CIRCUITS
- H03B5/00—Generation of oscillations using amplifier with regenerative feedback from output to input
- H03B5/20—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising resistance and either capacitance or inductance, e.g. phase-shift oscillator
- H03B5/22—Generation of oscillations using amplifier with regenerative feedback from output to input with frequency-determining element comprising resistance and either capacitance or inductance, e.g. phase-shift oscillator active element in amplifier being vacuum tube
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03F—AMPLIFIERS
- H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
- H03F1/34—Negative-feedback-circuit arrangements with or without positive feedback
- H03F1/36—Negative-feedback-circuit arrangements with or without positive feedback in discharge-tube amplifiers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
1,025,709. Amplifiers etc.; oscillators; frequency changers, MUIRHEAD & CO. Ltd. Jan. 23, 1964 [Feb. 8, 1963], No. 5132/63. Headings H3F and H3W. [Also in Division G1] An electronic oscillator or frequency selective amplifier in which the frequency of operation is determined by a resistance capacitance network in a positive feedback loop of an amplifier has a photo-sensitive element in the frequency determining network and means for varying the light falling on the element and therefore the frequency of oscillation, or operation, of the circuit. Fig. 1 shows one embodiment of a device for varying the intensity of illumination of a photo-sensitive element in which the mask 4 and an opaque disc 1 with transparent section 3 are interposed between a source of light and the photo-sensitive device, the rotation of the disc 1 controlling the light and therefore the operating frequency of the circuit. The mask 4 may be adjustable vertically to provide a zerosetting means. If a greater range of operation is required two discs geared to move in unison and with their transparent sections 3 crossing nearly perpendicularly may be provided, Fig. 3 (not shown), to give a variation of light intensity which is approximately the square of the variation provided by one disc alone. Alternatively the disc or discs may be replaced by film strips, Fig. 7 (not shown), one of which may have the frequency scale 38 photographically produced on its edge. The discs may also be replaced by a pair of polaroid plates one of which is turned relative to the other to modulate the light source. A low frequency oscillator circuit embodying the invention is shown in Fig. 10 in which photo-sensitive resistors 14 and 14<SP>1</SP> are subjected to the same illumination from a source 8 via a light modulating device not shown. The two photo-sensitive resistors may be replaced by a pair of fixed resistors having one photo-sensitive resistor connected between tapping points on the fixed resistors, in addition the push-pull output arrangement may be replaced by a transformer if the extreme low frequency range is not required (Fig. 5, not shown). The output signal of the oscillator may be modulated by providing a pendulum having an arcuate filter, opaque at its two extremities and linearly graded in optical density to transparency at its centre, arranged with the filter interposed between the light source and the mask in the frequency determining arrangement of the oscillator. When modulation is required the pendulum is maintained in oscillatory motion, the frequency of the swing being adjusted by adjustment of the pendulum bob weight. The light output of the source may be checked by having a further photo-sensitive resistor mounted to be illuminated by the light source and connected in a wheatstone bridge circuit which is balanced when the illumination is correct, the bridge output may be connected to automatically maintain the light output correct.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB5132/63A GB1025709A (en) | 1963-02-08 | 1963-02-08 | Resistance-capacitance type oscillators and selective amplifiers |
NL6401049A NL6401049A (en) | 1963-02-08 | 1964-02-07 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB5132/63A GB1025709A (en) | 1963-02-08 | 1963-02-08 | Resistance-capacitance type oscillators and selective amplifiers |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1025709A true GB1025709A (en) | 1966-04-14 |
Family
ID=9790309
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB5132/63A Expired GB1025709A (en) | 1963-02-08 | 1963-02-08 | Resistance-capacitance type oscillators and selective amplifiers |
Country Status (2)
Country | Link |
---|---|
GB (1) | GB1025709A (en) |
NL (1) | NL6401049A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3107446A1 (en) * | 1981-02-27 | 1982-10-21 | Gorenje Körting Electronic GmbH & Co, 8217 Grassau | Voltage-controlled sine-wave oscillator |
US4833419A (en) * | 1987-10-29 | 1989-05-23 | Henry Chrystie | Non-inductive radio apparatus |
-
1963
- 1963-02-08 GB GB5132/63A patent/GB1025709A/en not_active Expired
-
1964
- 1964-02-07 NL NL6401049A patent/NL6401049A/xx unknown
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3107446A1 (en) * | 1981-02-27 | 1982-10-21 | Gorenje Körting Electronic GmbH & Co, 8217 Grassau | Voltage-controlled sine-wave oscillator |
US4833419A (en) * | 1987-10-29 | 1989-05-23 | Henry Chrystie | Non-inductive radio apparatus |
Also Published As
Publication number | Publication date |
---|---|
NL6401049A (en) | 1964-08-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2907937A (en) | Digital servo system | |
GB1025709A (en) | Resistance-capacitance type oscillators and selective amplifiers | |
US4025190A (en) | Exposure control system for photographic copying | |
US3245083A (en) | Direct writing oscillograph | |
US3123724A (en) | Photosensitive light control system | |
GB1372337A (en) | Exposure control means | |
US3545870A (en) | Photometric apparatus incorporating light responsive transistorized switching circuit | |
US3743416A (en) | Optical image focusing device with audible indication | |
GB1281603A (en) | Photographic exposure control methods and apparatus | |
GB1258300A (en) | ||
GB1082788A (en) | Photo-recording apparatus | |
US3511574A (en) | Photometric apparatus having an intermittent signal at a select output state | |
US3146664A (en) | Indicia projection system | |
US2335621A (en) | Photometer | |
US2648782A (en) | Audio sweep frequency generator | |
US2279723A (en) | Photoelectric exposure determining | |
GB1288548A (en) | ||
US1849488A (en) | Multiplex transmission | |
US2593318A (en) | Photo and photo-transparency enlarging device | |
GB1085806A (en) | Improvements in or relating to enlarging exposure meters and electronic timers | |
US1940858A (en) | Sound recording and sound reproducing system | |
US2161369A (en) | Sound recording | |
JPS55133017A (en) | Light power control unit | |
US1923746A (en) | Modification of sound records | |
US2123115A (en) | Stroboscopic device for checking and adjusting meters |