SU1550437A1 - Device for measuring parameters of radio receiver when being tuned - Google Patents

Abstract

The invention relates to a radio metering technique and can be used to control parameters of radio receivers when they are tuned under mass production conditions. The purpose of the invention — an increase in tuning performance — is achieved by reducing the connection time and eliminating the time spent on controlling the local oscillator frequency. The software control unit 12 provides the maximum attenuation of attenuators 5 in N - 1 channels of interference signals and the minimum modulation level of modulators 4 in all N channels. The modulation frequency corresponds to the tuning frequency of the band-pass filter 9 connected to the output of the monitored radio receiver 8. An information code corresponding to the output signal at the main receiving frequency appears at the output of the voltage meter 10. The receiving frequency is determined by initializing the frequency meter 11. An information code corresponding to the receiving frequency is supplied to the display unit 13. The signals for the reception channels are generated by the generators 3 interference signals. The device also contains an intermediate frequency generator 1, a controlled generator of 2 signals of the fundamental frequency, a mixer 6 and a band-pass filter 7 of the signal — an intermediate frequency of the monitored radio receiver 8. 7 Il.

Description

Programs for measuring selectivity during radio tuning of interference channels are executed sequentially by program control unit 12 ((lg.1) after termination of the measurement program and display of sensitivity on the main reception frequency channel.

To do this, in each channel interference is made first by setting the appropriate frequency and modulation depth, and then attenuating the attenuator 5, at which the output of the corresponding filter 9 is set to the allowed signal level). At the same time, the level of the signal at the output of the main output frequency channel is checked and, if necessary, compensated for its decrease by attenuator 5 of the main reception channel. Information codes corresponding to the outputs on the outputs (the 9-channel noise channels are stored in the block) 2 software controllers and transmitted to the display unit J3 for displaying vertical lines at the appropriate scale, the heights of which are proportional to the voltages on the outputs of the respective Aylters, and the bases TC on the frequency axis and are spaced from the base of the main receive frequency line for the distance corresponding to the frequency difference between these channels.

The picture that the tuner sees on the screen of the display unit 13 is shown in (Fig. 7), where the graphical image of the obtained values of the parameters of the radio receiver is complemented by digital values, for example, senses

thirty

35

40

45

50

five

ka 8 inertia-free.

At the beginning of each cycle, a check is made to hold the main receiving frequency, for which the A / D converter 17 (Fig. 2) is polled. A sign of loss of reception frequency, which can occur when switching the reception range or quickly rebuilding its local oscillator, is the presence of a voltage of any sign at the output of the AaA detector 14.

When a loss of capture of the main receiving frequency is detected, the program transfers control to the part of it that provides the search and then captures the signal of the main frequency, preliminarily introducing the maximum attenuation across all interference channels and decreasing the attenuation through its main reception channel. At the end of the search and acquisition of the frequency of the main reception channel, the cyclic measurement and display parameters of the radio receiver 8 are restored.

Claims (1)

Invention Formula A device for measuring the parameters of a radio receiver when it is tuned, containing an intermediate frequency generator with an Adjustment input, p modulators, p controlled attenuators, a mixer, p bandpass filters, p voltage meters, a frequency meter, a program control unit and a display unit, with the mixer output connected to the input terminals of the receiver, n inputs of the mixer are connected to the outputs of the p attenuators, to the first inputs of which the outputs are connected application when adjusting the radio receiver5 0 five 0 five 0 five ka 8 inertia-free. At the beginning of each cycle, a check is made to hold the main receiving frequency, for which the A / D converter 17 (Fig. 2) is polled. A sign of loss of reception frequency, which can occur when switching the reception range or quickly rebuilding its local oscillator, is the presence of a voltage of any sign at the output of the AaA detector 14. When a loss of capture of the main receiving frequency is detected, the program transfers control to the part of it that provides the search and then captures the signal of the main frequency, preliminarily introducing the maximum attenuation across all interference channels and decreasing the attenuation through its main reception channel. At the end of the search and acquisition of the frequency of the main reception channel, the cyclic measurement and display parameters of the radio receiver 8 are restored. Invention Formula A device for measuring the parameters of a radio receiver when it is tuned, containing an intermediate frequency generator with an Adjustment input, p modulators, p controlled attenuators, a mixer, p bandpass filters, p voltage meters, a frequency meter, a program control unit and a display unit, with the mixer output connected to the input terminals of the receiver, n inputs of the mixer are connected to the outputs of the p attenuators, to the first inputs of which the outputs are connected FIG. 2 and H0 fig.Z IS and P8a Information highway FIG 4 Address line Search. Switch Address Code Code for the inclusion of the bypass TsN on the bypass of the VCO f: (frequency of reception received IDC Address Code DAC-F Informational Overview Y Time delay ADC Address Code Code Address code Pass code of the phase shifter discriminator with the VCO bypass ADC Address Code Not . max ADC in Y No Yes There is zakhbat FIG. 6 Wfb ZM 250 259 Fig 1J80