Editing Propagation Basics (section)

== Noise at the receiver ==
Whether a signal is readable depends on how far it sits above the receiving station's noise floor:
* '''Atmospheric noise''' dominates the low bands and is much stronger at night and in disturbed conditions.
* '''Man-made noise''' depends on the receiver environment; a city location can be tens of decibels noisier than a quiet rural one.
* Noise grows with receiver bandwidth: narrow modes hear deeper.