For those who might not be aware, there is now a dial-up telephone service for  The phone number, which is NOT toll free, is 712-432-4216.  Railroad Radio dot Net has operated a streaming website for many years, whereby listeners can here received radio transmissions by internet in almost real-time.  Dispatchers are commonly heard, as well as close-by yard switching operations, engineers operating from the locomotive cab radio, wayside defect detectors, an sometimes on-board conductors with walki-talkies if the train is extremely close by.  Anything you could hear with your scanner if you were at that location and had one, will come in either over your computer, smartfone, or now on any telephone.  

The available geographic locations are listed on the website, each one assigned a telco code.  This telephone hookup is an adjunct to what has already existed. 
The discrete three number code needs to be punched in after you dial the main number.  A prompt will ask you for that code. 

The new telephone dial up might be useful for some who have unlimited voice, but capped data plans.  It might be useful for mobile applications, where you would prefer to listen through the car radio speakers over a phone connection, as opposed to using a streaming service. 
Some of these channels are quite busy, and you will hear activity right away.  Be advised that others are not very busy, and there may be long periods of silence in between what trains do pass through a given area.