CS209207B1 - Apparatus for measuring of electroacoustic characteristics of magnetic carriers - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a device for measuring the electroacoustic properties of magnetic carriers, wherein various measurements of the magnetic carrier properties can be made by using a switching unit associated with some units of a stable measuring station.

So far, it has been necessary to connect the measuring workstation individually for each measurement when measuring the electroacoustic properties of magnetic carriers. The measurements could only be performed manually. For some measurements, such as overexertion and tape copying, it was time consuming to look for output voltage levels.

The measurements carried out in this way could not be used in the continuous control of production production, as they were very time-consuming. Moreover, the measurements did not allow the ratio expression of the measured quantities, which is necessary for the evaluation of the results by the printer.

The above disadvantages are overcome by the apparatus for measuring the electroacoustic properties of the magnetic carriers according to the invention. Its essence is that the recording part of the device consists of adjustable signal generators whose output is connected via dividers to the input of a line amplifier, which is connected to the measuring tape recorder, the first output of which is a current measuring unit of the recording head of the measuring tape recorder voltmeter. The evaluation part of the measuring device is connected to the second output of the measuring mag209207. This part of the device consists of an adjustable amplifier signal whose first output is routed directly to the control oscilloscope and recorder, and the second output is connected via band filters to ratio voltmeters, connected by their outputs to the measured value adjustment unit. The first output of the measured value adjustment unit is connected via a digital voltmeter to the measured value printer, and the second output of this unit is connected to the feedback loop via a controlled amplifier to the recording portion of the device at the second input of the divider unit. For individual measurements, the internal settings of some units are automatically controlled by the switching unit to the desired measurement function. The switching unit controls adjustable signal generators, a divider unit, a record head current measurement unit, a signal amplifier, band filters, ratio voltmeters, and a measured value adjustment unit.

Such a device allows that a single measuring workstation by different interconnections of individual units can be assembled to measure the following electroacoustic properties of magnetic carriers: relative pre-magnetization with operating point search, over-excitation, third harmonic distortion, relative sensitivity, high frequency relative sensitivity, modulation noise , resting noise, relative over-excitation at high frequencies, copying and erasability. In addition, the pre-magnetising current, the recording current and the DC current superimposed on the modulation noise measurement can be measured.

Measurements can be carried out automatically for operational purposes when they are measured at one point, and manually for laboratory purposes where the entire characteristic is measured depending on the pre-magnetising current. In the case of automatic measurement, the sequence of individual measurements is preset and some of them can be omitted as needed.

An example of the arrangement of the device according to the invention is shown schematically in the drawing.

The device consists of a recording part A and an evaluation part B. The recording part A consists of adjustable signal generators 1, the output of which is connected to the divider unit 2. The signal from the output of the divider unit 2 is routed to the input of the line amplifier 3. A tape recorder 5 with a digital voltmeter 6 is connected to the first output of the tape recorder 4.

The other output of the measuring tape recorder 4 is connected

Claims (2)

OBJECT <An apparatus for measuring the electroacoustic properties of magnetic carriers, characterized in that the recording part (A) consists of a set of adjustable signal generators (1) connected via a divider unit (2) to an input of a line amplifier (3). a tape recorder (4), the first output of which is a current measuring unit (5) of the recording head of the measuring tape recorder (4) connected to a digital voltmeter (6) and an evaluation part (B) connected to the second output of the measuring tape recorder ) is a variable amplification signal amplifier (7), the first output of which is routed directly to the control oscilloscope (8) and the recorder (9) and the second output of the amplifier This part is further comprised of a control oscilloscope 8 and a recorder 9, both of which are connected to the first output of the amplifier 7, to the second output of which the band filters 10 are connected. The ratio voltmeters 11 and 12. The ratio voltmeters 11 and 12 are coupled to the measured value adjustment unit 13, the first output of which is connected via digital voltmeter 15 to the printer 16. The second output of the measured value unit 13 is connected to the feedback loop via a controlled amplifier. 14 into the recording portion of the device A into the splitter unit 2. The signal generators 1, the divider unit 2, the recording head current measuring units 4, the signal amplifier 7, the band filters 10, the ratio voltmeters 11 and 12 and the measured value adjusting unit 13 are connected to the switching unit 17. The described equipment can be used both for orientation control in the production of magnetic tapes (automated measurement at one operating point) and for laboratory measurements (semi-automatic measurement of full characteristics) in accordance with common measurement standards. OF THE INVENTION (7) of the signal is connected via band filters (10) to ratio voltmeters (11 and 12) connected by its outputs to a measured value adjustment unit (13), the first output of which is connected via digital voltmeter (15) to a printer (16); the second output is connected to the feedback loop via a controlled amplifier (14) to the recording portion (A) of the device, to the second input of the divider unit (2), wherein the adjustable signal generator block (1), divider unit (2), unit (5) ) for measuring the recording head current, the signal amplifier (7), the band-pass filters (10), the ratio voltmeters (11 and 12) and the measured value adjusting unit (13) are connected to the switching unit (17).