SU449366A1 - Device for measuring the phase response of a magnetic recorder - Google Patents

Description

one

The invention relates to instrumentation. The device can be used when setting up and debugging magnetic recording apparatus, especially in the case when the phase ratio of the signals in such an apparatus is most important, such as, for example, in video recorders.

Devices are known for measuring the phase characteristics of magnetic recording apparatus, as well as characteristics indirectly related to the phase relationships of the recorded and reproduced signals (e.g., frequency signals). With all its diversity, the known devices are either very complex in design or do not provide the required measurement accuracy.

The purpose of the invention is to improve the accuracy of measurement of phase characteristics and simplify the device circuit.

The proposed device is characterized in that it is equipped with a reference pulse extraction unit and a parallel chain consisting of a sinusoidal oscillator, a reference pulse generator and a serially connected one-oscillator with a gating unit. A reference pulse extraction unit is connected between the output of the measuring magnetic recording apparatus and the input of the generator of rectangular pulses, and a chain is parallel between the output of the latter and the INPUT of the magnetic recording apparatus.

The drawing shows a block diagram of the device.

A generator of sinusoidal oscillations 2, a single vibrator 3 and a generator of reference pulses 4 are connected to the output of a generator of rectangular pulses 1. Each of them, respectively, through INPUTS 5, 6, 7 is connected to a general gating unit 8, in turn connected with the device

magnetic recording 9. The output of the latter is connected with a block for selecting reference pulses 10 and with an oscilloscope And through input 12. Two other inputs 13 and 14 of the oscilloscope are connected respectively to the input and output parallel to

chains consisting of generators 2 and 4 and one-shot 3 with gating unit 8. In the recording mode, the generator of sinusoidal oscillations 2, the one-shot 3 and the generator of reference pulses 4 receive a signal from the square-wave generator 1. In this case, the generator 2 generates its own signal arriving at input 5 of gating unit 8. At INPUT 6 of block 8, a pulse is fed from the one-shot 3, and to input 7 is a reference

pulse from generator 4. The signal generated in block 8 is recorded in the magnetic recording apparatus under test 9. Then the medium (not shown in the drawing) is rewound and the work is transferred to the playback mode. In this signal, through the reference pulse extraction unit 10 follows on

generator 1, operating in playback mode under conditions of external synchronization. As a result, all signals fall on the oscilloscope 11, in which the phase comparison takes place. The oscilloscope itself, through the input 13, is synchronized by pulses from a generator of rectangular pulses 1.

Subject invention

A device for measuring the phase characteristic of a magnetic recording apparatus, comprising a generator of rectangular pulses, the output of which is connected to one of the inputs of the oscilloscope, to the other two inputs of which connect the output and the input of the measuring magnetic recording apparatus, characterized in that simplify the circuit device, it

equipped with a reference pulse extraction unit and a parallel chain consisting of a sinusoidal oscillation generator, a reference pulse generator and a series-connected one-vibrator with a gating unit, while the reference pulse extraction unit is connected between the output of the measured magnetic recording apparatus and the input of the rectangular pulse generator, and parallel the chain is between the output of the latter and the input of the magnetic recording apparatus.