Editing Medium wave (section)

== Stereo and digital transmissions ==
{{See also|AM stereo|HD Radio|DRM30}}
[[File:Tandy AM Stereo.jpg|thumb|''Realistic'' TM-152 AM stereo tuner c. 1988]]
Stereo transmission is possible and is or was offered by some stations in the U.S., Canada, Mexico, the Dominican Republic, Paraguay, Australia, The Philippines, Japan, South Korea, South Africa, Italy and France.  However, there have been multiple standards for [[AM stereo]]. [[C-QUAM]] is the official standard in the United States as well as other countries, but receivers that implement the technology are no longer readily available to consumers.  Used receivers with AM Stereo can be found.  Names such as "FM/AM Stereo" or "AM & FM Stereo" can be misleading and usually do not signify that the radio will decode C-QUAM AM stereo, whereas a set labelled "FM Stereo/AM Stereo" or "AMAX Stereo" will support AM stereo.

In September 2002, the United States [[Federal Communications Commission]] approved the proprietary [[iBiquity]] [[in-band on-channel]] (IBOC) [[HD Radio]] system of [[digital audio broadcasting]], which is meant to improve the audio quality of signals.  The [[Digital Radio Mondiale]] (DRM) system standardised by ETSI supports stereo and is the ITU-approved system for use outside [[North America]] and [[United States territory|U.S. territories]].  Some HD Radio receivers also support C-QUAM AM stereo, although this feature is usually not advertised by the manufacturer.