Channels 3 and 7 plan to launch new programming to fight back against rivals after facing a decline in viewership caused by the emergence of digital TV.
Surin Krittayapongpun, vice-president of BEC World Plc, the operator of Channel 3, said the company would revise its weekend programming by mid-year to attract more viewers.
Channel 3 Analogue has a simulcast on the digital platform and has transformed itself into Channel 3 Original. Its shows are aired on a high-definition channel.
The airtime slots on weekdays will be strengthened by soap operas featuring superstars. Channel 3 Original will broadcast 50 soap operas to fill 7,000 hours a year.
"Although our audience has diminished, we're still near the top for TV viewership, which should encourage media agencies to choose us as their major TV channel for advertising," Mr Surin said.
Channel 3 SD, a standard-definition variety digital channel, will be enhanced with new sports programming such as Uefa Euro 2016 qualifying matches and the 2015 Grand Prix motorcycle racing season, airing during prime time.
The new content is aimed at viewers who do not watch soap operas. This group will attract new advertisers that target this customer segment.
Channel 3 Family, BEC's children's channel, will introduce new content in collaboration with content provider Turner International Asia Pacific.
Pogo, a cartoon based on the long-running American comic strip, will air from 4-6pm on weekdays and 7-9am on weekends.
The children's channel has adopted a marketing scheme to draw advertisers by lowering airtime rates.
"It's not easy to develop a popular new TV channel when the broadcasting business has heavy competition," Mr Surin said.
Digital TV will celebrate its first anniversary next week, but the broadcasting industry still faces uncertainty.
Some operators of the 24 digital channels remain in the red as they struggle with high fixed costs.
Last year, BEC World reported a 1-billion-baht loss blamed on high costs from licence fees, network rents and content production.
Mr Surin hopes to cut the company's losses this year.
Meanwhile, Palakorn Somsuwan, managing director of Bangkok Broadcasting and Television Co, the operator of Channel 7, said the company would focus on programme rescheduling in non-prime-time slots.
Channel 7 has been doing marketing to reinforce its positioning and dedication to quality content.
It remains the top-ranked TV channel with a 25% viewership, while Channel 3 ranks second with 21%.