Note that the BBC World Service presents its emissions in Mongolian with bulletins "information in English with Mongolian broadcastings. CFI (Canal France International) and TV5 broadcast in French. 
It is best to stock up on stamps before leaving the capital. And deposit their mail at the post office directly, rather than a hotel reception or in the public boxes. 
A letter to abroad is one to two weeks before reaching their destination.
To call Ulaanbaatar, dial 00 976 and the number of your correspondent. You can obtain international calls direct to the Central Post Office and major hotels in Ulaan Baator. 
The post office sells phone cards for international calls. Mobicom, Unitel, G-Mobile and Skytel are main telecommunication companies.