SU371556A1 - ALL-UNION TITLE 1 ^ t '^ y iv ^ g - Google Patents

Description

one

The invention relates to devices for receiving accurate time signals, in particular, for correcting the readings of time devices with second and minute counts, correcting for watch stations, as well as for correcting hours of widespread use.

A known device for receiving accurate time signals includes an audio output frequency of a broadcasting channel transmitting accurate time signals, a band-pass filter tuned to a frequency of time signals of 1000 Hz, a detector, a low-pass filter, a time selector, and a clock correction actuator.

However, when receiving signals by such a device, the possibility of passing a series of spurious pulses having a frequency close to or equal to the frequency of filling the exact time signals is not excluded. In addition, the device does not provide the ability to receive accurate time signals against the background of the transmission of music and speech signals.

The purpose of the invention is to improve the noise immunity and reliability of receiving accurate time signals.

This is achieved in that the device is equipped with a synchronous detector, one of the inputs of which is connected with the output of the bandpass filter, and its second input with the output of the second bandpass filter. The inputs of both bandpass filters are separately connected to the outputs of two unrelated broadcasting channels broadcasting different programs and identical time signals.

In order to compensate for the time lag of one time exact signal (From the channels relative to the other, a phase shifter is connected between the band-pass filter and the input of the synchronous detector of one of the channels.

The drawing shows a block diagram of the proposed device for receiving signals of exact time. Two audio output

of broadcasting channels U and 2, broadcasting programs and identical time signals, are connected separately through band-pass filters 3 and 4 and through a phase shifter 5 to the inputs of a synchronous detector 6. The output of a synchronous detector via a low-pass filter 7 and a time selector 8 is connected to the correction correction actuator 9 .

The device works as follows.

Audio frequency signals from the outputs of broadcasting channels 1 and 2, on which different programs and identical time signals are broadcast, are separately fed to band-pass filters 3 and 4 to extract the frequency of filling the exact time signals. The electrical signal from the band-pass filter 3 is fed to one of the inputs of the synchronous detector 6, the electrical signal from the band-pass filter 4 to the other input of the synchronous detector 6 through the phase shifter 5. In this case, the average value of the signal at the output of the synchronous detector is different from zero when both inputs There are identical signals, which are only time signals. All other signals that do not coincide in frequency and phase, at the output of the synchronous detector 6, do not have a constant component. The electrical signals from the synchronous detector 6 are fed to a low-pass filter 7, in which the high-frequency components are delayed.

The proposed device eliminates the reception of spurious signals, makes it possible to receive accurate time signals against the background of broadcasts, and also provides cost savings due to the use of band-pass filters with a goodness below ten.

Subject inventions

Claims (2)

1. A device for receiving accurate time signals transmitted over broadcasting channels, comprising a band-pass filter, a detector, a low-frequency time selector and a clock correction control, characterized in that, in order to improve the noise immunity and reliability of receiving exact time signals, it is equipped with a synchronous detector, one of the inputs of which is connected to the output of a bandpass filter, and its second input is connected to the output of a second bandpass filter, the inputs of both bandpass the filters are separately connected to the outputs of two unconnected broadcasting channels broadcasting different programs and identical time signals. 2. The device according to claim 1, characterized in that, in order to compensate for 1 and delay the time signal on one of the channels relative to the other, a phase shifter is turned on between the band-pass filter and the input of the synchronous detector of one of the channels.