Audio System

How the Vehicle Audio System Works

AM and FM signals are transmitted through relay stations located around the city. The signals from them are received by the vehicle antenna.

When a strong radio signal is received by the radio antenna, the modern audio system provides high-quality reproduction. However, in some cases the incoming signal is weak and unclear. This may be caused by distance from the radio station, proximity to other radio stations, or the presence of buildings, bridges or other large objects in your area.

Generally, AM reception is better than FM reception. This is because AM radio waves are transmitted at low broadcast frequencies. Long, low-frequency radio waves can propagate in the atmosphere both in a straight line and by following the curvature of the earth's surface. Moreover, they can bend around various objects and provide better radio coverage.

As a result, clear AM reception can be achieved over longer distances than FM reception.

AM Radio Wave Propagation

FM radio waves are transmitted at high broadcast frequencies and cannot follow the earth's surface. As a result, FM radio waves generally begin to weaken over a short distance from the transmitting station. FM radio waves are more strongly affected by buildings, mountains or other objects. This may degrade reproduction quality, and you may mistake this for a radio malfunction. The following conditions are normal and do not indicate a radio malfunction:

FM Radio Wave Propagation

FM Radio Wave Propagation in Different Terrain

– Fading – as the vehicle moves away from the radio station's transmitting antenna, the radio signal strength decreases and the sound begins to fade. In this case, it is recommended to select another station with a stronger signal;

Fading of the FM Signal as the Vehicle Moves Away from the Radio Station's Transmitting Antenna

– Constant buzzing noise – a weak FM radio signal or large obstacles between the radio transmitter and the vehicle receiving antenna cause interference in the form of constant buzzing noise. This effect can be reduced by lowering the treble tone control level;
– Multipath interference – as the FM signal weakens, another stronger signal with a close broadcast frequency may appear. This occurs when the tuning system is set to the clearest signal of the radio. In this case, switch to another station with a stronger signal;

Multipath Interference as the FM Signal Weakens and Another Stronger Signal with a Close Broadcast Frequency Appears

– Interference noise – radio signals received from different directions reaching the vehicle antenna may cause constant buzzing noise. This may be caused by the direct signal from a radio station and a reflected signal from the same station, or by two signals from stations broadcasting on close frequencies, reaching the vehicle antenna. In this case, switch to another station until these conditions disappear.