AUGUSTA –Starting today, Time Warner Cable viewers in Augusta and surrounding communities will no longer be able to tune in without a digital conversion box.

Time Warner Cable is converting the remaining analog channels in its lineup to an all-digital format in 21 central Maine communities.

Customers in those communities need a digital adapter or digital set-top box to continue to receive TV programming, which includes shows offered by local ABC, CBS, NBC, FOX and PBS affiliates, and such cable channels as ESPN, MTV and New England Sports Network.

Sunday’s football game between the New England Patriots and Baltimore Ravens falls into that programming list, too.

Most people already have obtained digital adapters, according to a prepared statement from Time Warner Cable. Residential customers can get digital adapters free through December 2013.

Starting January 2014, digital adapters will cost 99 cents a month each.

The adapters are available in Augusta, Winslow, Lewiston, among other sites, by calling 1-855-TWC-DIGITAL (855-892-3444) or by ordering then online at www.timewarnercable.com/GoDigital.

With a digital adapter, customers with the basic cable package receive up to 14 additional channels, including C-SPAN2, EWTN and PBS World. Customers with the classic/standard package will receive those channels plus CMT, TruTV, Oxygen, Travel and Speed.

The transition to digital allows additional capacity to the network, according to Time Warner officials.

Time Warner Cable launched the transition to the all-digital format last fall in 105 communities. In the first phase, the company digitized 23 channels on the basic and classic/standard channel tiers.

Now, Time Warner Cable is digitizing the 40 remaining analog channels, including local broadcasters, such as WCSH, WGME and WMTW.