CBC will continue to broadcast analog over-the-air television signals from 22 transmitters that could have been shut down after the mandatory changeover to digital TV on Aug. 31.

The CRTC, the federal broadcast regulator, announced Tuesday that it had approved a plan by the public broadcaster for analog transmission to continue in these areas until Aug. 31, 2012.

English-language signals affected by the extension include those in Saskatoon, London, Ont., and Quebec City.

In 2007, the Canadian Radio-television and Telecommunications Commission set Aug. 31, 2011 as the deadline for broadcasters to complete the transition from analog to digital television.

The regulator made the transition mandatory in 28 Canadian towns and cities, including provincial and national capitals, metropolitan areas with populations greater than 300,000, and markets served by more than one local television station.

The CBC will convert 27 local stations in mandatory markets to digital in time for the deadline.

But it also operates 22 analog transmitters that rebroadcast its stations' signals into other communities where it does not plan to replace the analog transmitters with digital ones. The CBC does not have a local station in these cities and towns.

Canadians who receive television via satellite or cable providers will not be affected by the change and will continue to receive a signal. But those who continue to use an aerial or rabbit ears to receive over-the-air analog TV would have lost their signal after Aug. 31. The CRTC estimates that may be from 7.5 to 13 per cent of Canadians.

London, Ont., Mayor Joe Fontana wrote to CBC earlier this year asking the public broadcaster to reconsider its plan to shut down its analog transmitter without installing a digital replacement, saying about 30,000 London residents and many more in rural areas would be affected.

Local residents argued "they should have a right to receive digital television from the national broadcaster since they subsidize the CBC/Radio-Canada through their taxes," he said in the letter to CBC president Hubert Lacroix.

In his reply, Lacroix said the CBC believes use of over-the-air signals will continue to decline and the CBC plans to enhance "our regional programming offer on multiple platforms."

The CBC will continue to operate more than 600 analog transmitters across Canada, including across the Canadian North, according to CBC spokesman Angus McKinnon.

"It raises a question of affordability," he said Tuesday. "That is an issue CBC has raised with the CRTC."

CBC has spent $60 million so far in the transition to digital and additional digital transmitters might not be the most responsible use of taxpayers' dollars moving forward, he said. Instead, CBC plans to invest in new digital platforms, including mobile and internet, he said.

"More people are watching TV online than over the airwaves," McKinnon said. "We expect over-the-air use to continue to decline."

The additional year of analog transmission is good news because it allows people time "to transition to new means of getting programming without hardship," he said.

The CRTC has asked the CBC to use the coming year to find alternative solutions for markets where it will not be installing a digital transmitter.

The federal government plans to sell off the spectrum cleared by the switch to digital.