| Only a buzzing sound from the speakers |
- There is no broadcasting wave.
- Signals from antenna to audio unit are not transmitted.
|
- Electric noise caused by the operation of internal circuit from audio unit it self
- Atmosphere noise
|
| A buzzing or crunching sound and normal sound produced at the same time from the speakers |
- Though signals are transmitted from antenna to audio unit, electric noise from other sources is larger.
|
- Electrical noise caused by operation of electrical component on vehicle
- Electrical noise from high tension wire, transformer substation (factory), electrical feeder line (street car), or motorcycle.
|
| A thumping sound and normal sound produced at the same time from the speakers (FM only) |
- Noise occurs due to radio wave environment at specific places (e.g. in valleys between buildings). Noise varies when own vehicle or surrounding vehicles moves. (FM only)
|
- Interference between direct and reflected waves of FM signals causes noise (Multipass noise).
|