SU692111A1 - Digital servo scanning signal former - Google Patents

Description

The invention relates to television and can be used in television measuring systems using transmitting tubes without accumulating charges.

A digital tracking digital signal driver is known, comprising a scanning register, a serially connected digital-to-analog converter and a scanning signal amplifier 1.

However, in a well-known digital servo signal generator, no sweep signal is corrected.

The purpose of the invention is to provide correction of the sweep signal.

For this purpose, a digital sweep signal generator containing a scan register, serially connected digital-to-analog converter, and a scanning signal amplifier, serially connected angular displacement sensor, phase-sensitive amplitude detector and analog-to-digital converter, as well as a delay unit, code adder and memory register , while the output analog-to-digital converter

connected to the first input of the code adder, the second input of which is connected to the output of the sweep register, the counting input of this register is connected to the first output of the delay block and the input of setting the zero of the code adder, the input of the recording resolution of the coordinate code and the input of the recording resolution of the correction code which are connected respectively to the second and the third output of the delay unit, the fourth output of this block is connected to the input of the write resolution of the memory register, the information input of the latter is connected to the output of the code adder, the output of the register n This is connected to the input of a digital-analog converter, and to the input

Claims (1)

5 block delay clock pulses. The drawing shows a structural electrical circuit of the proposed device. The digital sequential sweep signal generator contains an angular displacement sensor 1, a phase-sensitive amplitude detector 2, an analog-to-digital converter (Au, P) 3, an adder 4 codes, a sweep register 5, a memory register 6, a digital-to-analog converter (D / A) 7, an amplifier 8 the sweep signal, delay block 9, and deflecting coil 10. The shaper operates as follows. The instantaneous platform tilt angle value at this coordinate is measured by the angular displacement sensor 1, the signal of which is demodulated by the phase-sensitive amplitude detector 2 and converted into correction code by analog-to-digital converter 3, the output of the latter is connected to the input 2 of the second adder of 4 codes. Input "the first adder of the adder 4 codes connected to the output of the register 5 sweep. On each scan sweep corresponding to a change in the code on the scan register 5 per unit of the youngest bit, in the adder 4 of the codes, the code of the coordinate of the scan register 5 with the correction code of the deviation of the analog-to-digital converter .3 followed by the transfer is algebraically (taking into account the sign of the correction code). The result code for the register is 6 memory. The result code is converted into analogue by a digital-to-analog converter 7, from its output the analog voltage of a stepwise sawtooth form is fed to the amplifier 8, the load of which is the deflection coil 10, as a result, the current in the deflection coil 10 at each time instant corresponding to the sweep step, is proportional to the code of the result of the addition at the output of the adder 4 codes, and therefore it is proportional to the amount of deviation of the aperture on the photocathode of the tube. The delay unit 9 performs a time shift of the clock sequence necessary for the correct operation of the driver. From the first output of the Q delay block, the pulses coinciding with the input (zero delay) are fed to the input of the zero setter of 4 codes, resetting the summation result in the previous clock and to the counting input of the sweep register 5, advancing it to the unit of the least significant bit. From the second output of the delay unit 9, the pulses delayed relative to the input for time T are input to the write resolution of the first adder of the adder 4 codes, while the coordinate code from the sweep register 5 is transferred to the adder 4 codes. From the third output of the delay unit 9, the pulses delayed by 27 relative to the input ones are input to the recording resolution input of the second term of the adder 4 codes, the deviation correction code is transferred from the analog-digital converter 3 to the 4 code adder, and an algebraic operation is performed. From the fourth exit. The delay unit 9 delayed by the ZG pulses are fed to the input of the write resolution of the memory register 6, allowing the result code to be written to the memory register from the output of the 4 code adder. The delay time T must be sufficient to terminate the transients in the 4-code adder. Due to the fact that at each step of moving the position of the projection of the aperture on the photocathode of the transmitting tube is determined not only by the sweep register code 5, but also by the deflection correction code, the mutual displacement velocity of the object and aperture projections along the photocathode (up to the error of the deflection correction code) is zero, and the time of coincidence of the projections and aperture is equal to the interval between clock pulses, i.e. the time of their coincidence with a fixed projection of the object. Reducing the speed of the object and aperture relative to zero almost to zero determines the preservation of the sensitivity of the television system when there are practical values of the frequency and range of oscillations of the object projection and the duration of the clock sweep interval. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention includes a digital servo sweep signal generator comprising a sweep register, a serially connected digital-to-analog converter and a scanning signal amplifier, characterized in that, in order to provide correction of the scanning signal, serially connected angular displacement sensor, a phase-sensitive amplitude detector and an analog-digital converter are introduced, as well as a delay unit, a code adder and a memory register, with the analog-to-digital converter output connected to the first input a code adder, the second input of which is connected to the output of the sweep register, the counting input of this register is connected to the first output of the delay unit and the input of the zero input of the code adder, the input of the coordinate code recording resolution and the input of the resolution of the correction code which is connected to the second and third output delay, the fourth output of this block is connected to the memory register write enable input, the information input of the latter is connected to the output of the code adder, the output of the memory register is connected to the input ohm digital-to-analog converter, and clock pulses are applied to the input of the delay unit. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 2340084 / 18-09, cl. H 04 N 3/22, 1976 (prototype).