Parking sensors with sound indication

Only sound

— as the name implies, the only signal provided in such parking sensors is sound. An intermittent signal is traditionally used: it turns on at a low frequency when an obstacle appears in the sensor coverage area, increases the frequency as it approaches, and when the distance becomes less than the minimum working distance, it turns into a continuous one, signaling a dangerous approach. The main advantages of such an indication are low cost, as well as ease of design and installation. On the other hand, the beep only gives a very rough idea of the distance and usually does not tell which side (left or right) the sensors are triggered. As a result, you either have to connect an external monitor (many of these models provide such an opportunity), or learn to assess the situation by the sound frequency.