Will the use of cell phone signal jammers in campus examination rooms affect the timekeeping of radio-controlled clocks? from dojammer's blog

The use of cell phone signal jammers in examination rooms is now basically standard, and it is common and not surprising. When you enter the examination room, you will also find a common device, that is, a radio-controlled clock. Radio-controlled clocks, as the name suggests, are clocks that display time, but radio-controlled clocks are not simple clocks. Radio-controlled clocks are clocks that ensure the accuracy of time by receiving wireless signals from the National Time Service Center. They are much more advanced than ordinary clocks.

The signal blocked by the cell phone signal jammer is the wireless signal, so will the mobile phone signal jammer interfere with the radio-controlled clock? To understand whether the cell phone signal jammer interferes with the radio-controlled clock, the first thing to understand is the frequency used by the radio-controlled clock when receiving the wireless signal from the National Time Service Center. Radio-controlled clocks receive signals from the National Time Service Center in two general ways: one is to receive the timing signal through GPS, and the other is to obtain the timing signal through 4G signals. The signal emitted by the mobile phone signal jammer does not contain the GPS signal frequency, so it will not interfere with the GPS timing signal received by the radio clock. When another type of radio clock obtains the timing signal through the 4G signal, the cell phone signal jammer will interfere with the radio clock when it obtains the timing signal, but there is no need to worry about the large error in the time displayed by the radio clock.

When the radio clock receives the timing signal, it is mainly used for the time calibration of the radio clock. The cell phone signal jammer does not affect the normal use of the radio clock, and the radio clock still displays the current time according to the normal time even when it does not receive the timing signal. Even if the radio clock is interfered by the shielding signal of the cell phone signal jammer, it will not cause a large error in the time display of the radio clock. Because even if the radio clock cannot be calibrated through the timing signal for more than half a year, the error between the time displayed by the radio clock and the standard time is extremely low and can basically be ignored.