Abstract A system for producing a horizontal deflection drive pulse having a closely regulated duration. A driver transistor is coupled to the primary winding of a transformer, and is adapted to receive periodic pulses from an oscillator. A second, timer transistor is operated by signals derived from a secondary winding of the transformer and serves to regeneratively drive the first transistor into full conduction. An R-C timing circuit coupled to the base of the timer transistor serves to determine the period of time for which the timer transistor maintains the driver transistor in a conductive state. The duration of the pulse produced by the driver transistor is thus primarily a function of the R-C timing circuit characteristics, and remains substantially constant in the presence of variations in supply voltage, in the characteristics of the driver or timer transistors, or in the presence of variations in the waveshape of the periodic pulses provided by the oscillator.
In a television receiver cathode ray beam deflection system, controlled width pulse producing means for causing periodic beam deflection comprising: first switch means, second switch means, first coupling means regeneratively coupling said first switch means to said second switch means, second coupling means regeneratively coupling said second switch means to said first switch means, said first switch means being responsive to sync pulses developed within said television receiver by changing its state of conduction in response to each such sync pulse, said first coupling means applying a signal to said second switch means indicative of the change of state of conduction of said first switch means to cause said second switch means to change its state of conduction, said second coupling means applying a signal to said first switch means indicative of the change of state of conduction of said second switch means to enhance the changing of state of conduction of said first switch means, said first coupling means including timing means to maintain said second switch means in its assumed state of conduction for a predetermined period of time, said second switch means returning to its original state of conduction at the end of said predetermined period, said first and second coupling means regeneratively driving said first and second switch means to their original states of conduction when said second switch means begins to return to its original state of conduction at the end of said predetermined period, said first switch means including output circuit means for outputting a pulse having a width determined by said timing means.
Claim 2
Dependent Claim
260 words
In a television receiver cathode ray beam deflection system, controlled width pulse producing means for causing periodic beam deflection comprising: first switch means, second switch means, first coupling means regeneratively coupling said first switch means to said second switch means, second coupling means regeneratively coupling said second switch means to said first switch means, said first switch means being responsive to sync pulses developed within said television receiver by changing its state of conduction in response to each such sync pulse, said first coupling means applying a signal to said second switch means indicative of the change of state of conduction of said first switch means to cause said second switch means to change its state of conduction, said second coupling means applying a signal to said first switch means indicative of the change of state of conduction of said second switch means to enhance the changing of state of conduction of said first switch means, said first coupling means including timing means to maintain said second switch means in its assumed state of conduction for a predetermined period of time, said second switch means returning to its original state of conduction at the end of said predetermined period, said first and second coupling means regeneratively driving said first and second switch means to their original states of conduction when said second switch means begins to return to its original state of conduction at the end of said predetermined period, said first switch means including output circuit means for outputting a pulse having a width determined by said timing means.
Claim 3
Dependent Claim
32 words
The invention as claimed in claim 1 wherein theoriginal state of conduction of said first switch means is OFF and the original state of conduction of said second switch means is ON.
Claim 4
Dependent Claim
50 words
The invention as claimed in claim 2 wherein said second coupling means includes means to bias said first switch means, said second switch means being coupled to said bias means to change the biasing of said first switch means when said second switch means is in the ON conductive state.
Claim 5
Dependent Claim
44 words
The invention claimed in claim 3 wherein said first coupling means includes a transformer, one secondary winding thereof being coupled to the input of said second switch means and the second secondary winding thereof comprising the output circuit means of said first switch means.