XM SATELLITE RADIO TEAMS WITH BET, RADIO ONE AND SYNCOM TO CREATE URBAN RADIO CHANNELS FOR THE SATELLITE SERVICE

Nation's Largest Broadcasters and Venture Capital Firm Serving the African-American Community Join XM.

National, December 15, 1998 -- Hugh Panero, XM Satellite Radio Inc.'s President & CEO, today announced an exclusive programming deal to create African-American talk and music channels with Black Entertainment Television Inc. (BET), Radio One, Inc. (Radio One) and Syndicated Communications, Inc. (SYNCOM).

"These media companies represent the premiere television, radio and venture capital firms in the United States that are owned by and serve the African-American community," said Mr. Panero. Under the terms of the BET and Radio One agreements, XM will offer four channels -- African-American Talk, Gospel, Hip Hop/Rap and Adult Contemporary music -- that will be exclusively branded with the BET name and created in conjunction with Radio One, in which SYNCOM is a significant investor.

"We are excited to be a part of the XM Satellite Radio service and to extend the BET brand name into the world of radio," said Robert L. Johnson, Founder, Chairman and CEO of BET Holdings, Inc., which owns BET and is the country's leading media company targeting African-American consumers. "Our involvement with XM is consistent with BET's strategy to be on the cutting edge of entertainment and new technology."

Alfred C. Liggins, III, CEO and President of Radio One, added, "XM Satellite Radio represents the next generation of radio. As the nation's largest radio company primarily targeting African-American listeners, we want to extend further our franchise, both on a local level as well as on a national scale, utilizing this new satellite technology."

"We are very enthusiastic about the synergy created by these companies working together," said Terry Jones, General Partner, SYNCOM, a leading minority-owned venture capital group and major investor in Radio One. "Through our alliance, we will offer the best entertainment, news and information programming created by and for African-Americans from coast-to-coast."

Mr. Panero commented, "I could not be happier being associated with leading African-American-owned media companies like BET, Radio One and SYNCOM, particularly at a time minority voices seem to be dwindling. leading like BET, Radio One and SYNCOM, particularly at a time in the radio business when minority voices seem to be dwindling. This is a relationship that will surely be expanded over time."

BET Holdings, Inc. is a multi-media entertainment company which owns and operates Black Entertainment Television (BET), the first national cable network targeted toward African-American consumers. BET is currently available in 55 million households according to A. C. Nielsen media research. The parent company of Black Entertainment Television and three other cable television networks, BET Holdings, Inc. has subsidiaries that include book and magazine publishing, restaurants, financial products, retail clothing and an interactive website.

Radio One is the nation's largest radio broadcasting company targeting African-American listeners. Pro forma for recently announced acquisitions, the company will own and operate 14 radio stations, primarily in five urban markets in the United States, including highly rated stations in both the Washington, DC, and Baltimore, MD, markets. Additionally, Radio One of Atlanta, Inc., a related company that has recently filed with the FCC for approval to be acquired by Radio One, owns and/or operates two radio stations in the Atlanta, Georgia market.

SYNCOM specializes in telecommunications and media related investments throughout the United States. SYNCOM's venture holdings include radio, cable TV, satellite and new-media companies that target services to the nation's urban and ethnic markets.

The BET/Radio One channels join XM's brand-name channel lineup, which includes USA TODAY, the nation's largest selling newspaper; Bloomberg News Radio, the country's leading source for financial news; Heftel Broadcasting Corporation, the country's largest Spanish language radio broadcaster; Salem Communications Corporation, the nation's premier Christian broadcaster; AsiaOne, a major provider of Asian news and entertainment; and C-SPAN Radio, to provide its signature audio coverage of public affairs events on Capitol Hill and around the country, often live.

XM Satellite Radio Inc. is owned by American Mobile Satellite Corporation (NASDAQ:SKYC) and WorldSpace, Inc. Formerly called American Mobile Radio Corporation, the company obtained a satellite digital audio radio service (SDARS) licenses from the FCC in October 1997. In March 1998, XM awarded a contract to Hughes Space & Communications International and Alcatel to build two high-powered, direct-broadcast satellites. In November 1998, Alpine Electronics, Inc., Pioneer Electronic Corporation, and the Sharp Corporation announced that they will manufacture and distribute XM-capable radios and audio systems for the US market. In addition, XM satellite construction is on schedule, and the company recently completed terrestrial repeater technology testing in Washington, D.C., and Germany. XM plans to launch its satellites and begin providing up to 100 channels of digital audio service with crystal-clear sound from coast-to-coast in 2000. XM's selection, quality and convenience will make it America's first choice in audio entertainment. For more information, please visit XM's website at www.xmradio.com.

In September 1998, Mr. Panero announced the company's name change from American Mobile Radio Corporation (AMRC) to XM Satellite Radio Inc. In November, the company signed agreements with Alpine Electronics, Inc., Pioneer Electronic Corporation, and the Sharp Corporation to manufacture and distribute XM-capable radios and audio systems for the U.S. market.

XM Satellite Radio Inc. is owned by American Mobile Satellite Corporation (NASDAQ:SKYC) and WorldSpace, Inc. The company obtained one of two satellite digital audio radio service (SDARS) licenses from the FCC in October 1997. In March 1998, XM awarded a contract to Hughes Space & Communications International and Alcatel to build two high-powered, direct-broadcast satellites. In addition, XM satellite construction is on schedule, and the company recently completed terrestrial repeater technology testing in Washington, D.C., and Germany. XM plans to launch its satellites and begin providing up to 100 channels of digital audio service with crystal-clear sound from coast-to-coast in 2000. XM's selection, quality and convenience will make it America's first choice in audio entertainment. For more information, please visit XM's website at www.xmradio.com.

XM, BET, Radio One, SYNCOM, American Mobile and WorldSpace are all based in the Washington, DC, area.

Press Contacts
Jennifer Markham
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