American broadcasters have finally bowed to political pressure and accepted a 2009 switchover date for digital-only transmission.

The National Association of Broadcasters is, however, keen for Congress to mandate that cable companies continue to provide a post-switchover analog signal for those viewers with older television sets; but cable officials prefer to choose whether or not to broadcast low-rating channels via analog.

National Cable & Telecommunications Association president/ceo Kyle McSlarrow expressed concern that carrying multiple signals would force other programming and services out of the marketplace: "We have one pipe, upgraded with fiber-optic technology, with very robust capacity, but it is not unlimited."

Under current law broadcasters are required to cease analog transmissions at the end of 2006, but exceptions have been granted for markets where less than 85% of TV viewers receive a digital signal.

One of the hurdles to setting a switchover deadline is that only 5 million homes presently have digital cable TV sets or a digital tuner. A subsidy program is being reviewed for the purchase of converter boxes for those 15% of viewers with analog sets.

The digital transition will enable the government to auction channels on the analog spectrum to wireless companies, reaping up to $30 billion (€24.8bn; £17.1bn). It will also free up spectrum for the upgrading of emergency services communication.

Data sourced from USA Today Online; additional content by WARC staff