The CBC will get another chance to explain why it should be allowed to sell advertisements on two of its radio networks when the corporation makes a presentation to Canada’s telecommunications regulator on Friday.

For more than a week, the CRTC has been hearing from those who have weighed in on the CBC’s bid to renew the licences for its various services for the next five years. One of the most contentious issues is a plan by the corporation to begin running ads on its English-language Radio 2 network and French-language Espace Musique.

The plan is facing stiff opposition from some of the CBC’s competitors.

On Thursday, the CRTC heard several submissions from broadcasters opposed to the proposition.

"I’ve got a lot of difficulty getting my head around an organization that can’t work on a billion-dollar-plus budget," said Ross Porter, a former CBC host who is now president and CEO of Jazz FM 91, a Toronto radio station.

"I’ve got a hard time with them going out there and double-dipping and asking for donations from the Canadian public."

Adam Fox, from Alberta public radio station CKUA, also voiced concern with the CBC plan. He said ad dollars on top of government funding will give the CBC an unfair advantage.

"CKUA is not afraid of competition, but this isn’t really a fair fight," he said. "The playing field is pitched dramatically in favour of Radio 2 and its clearly superior resources."

The Canadian Association of Broadcasters submitted its own written brief to the CRTC, urging it to reject ads on CBC Radio and calling the idea "ill-conceived."

"The Radio Council is seriously concerned that approval of this application could, over time, create a precedent for the CBC to extend this request to other CBC radio services, including locally-based CBC Radio One and La Premiere Chaine," the broadcasters wrote.

The CBC had its financing cut by $115 million in the last federal budget. The corporation says running ads and allowing program sponsorship on Radio 2 and Espace Musique could provide $15 million in additional revenue in the first year and up to $35 million within seven years.

In his presentation to the CRTC last week, CBC president Hubert Lacroix warned the commission that if its request was rejected the corporation would have to find money elsewhere.

"We have no intention of closing those radio stations down but they will change in format and content," Lacroix said. "It is going to be about the whole of the services of CBC, Radio-Canada being affected by this decision."

Lacroix and other CBC bosses are expected to be back before the CRTC Friday to answer more questions as the commission wraps up its hearings. The CRTC will then consider the arguments and issue a decision by the spring.