The City believes that Schoonmaker's departure raises questions about Emap's commitment to the sector and uncertainty at the top of the £2.3bn group about strategy.
Schoonmaker, who spent more than 20 years at Emap, is understood to have told friends that he wants to take advantage of the deregulation of the radio market. This could include a bid for Emap's radio business or for a rival radio group.
City sources have said that there will be a number of willing buyers for Emap's radio assets and a deal involving Schoonmaker was possible.
"There would certainly be willing buyers for Emap's radio assets. Schoonmaker could tie up with a venture capital group and lead a bid for them. Or the whole group could be snapped up and the parts sold separately. It's not cheap but its assets are very attractive," a senior City source told the Mail on Sunday.
If Schoonmaker teamed up with venture capitalists to bid for another radio group, possible targets include Capital Radio, which has seen its share price fall along with audience numbers, and GWR, according to analysts. Venture capital groups that are active in the media sector include Apax Partners and Candover.
Whereas Emap denies that Schoonmaker left on bad terms, there is speculation that he may have fallen out with Emap chief executive Tom Moloney about ambitions to bid for the radio assets of SMG, which includes Virgin Radio and a 27% stake in Scottish Radio Holdings. Some company insiders claim that Moloney, who moved up Emap's ranks through magazines, was unwilling to fund the deal.
Emap owns Kiss 100, Magic and The Big City Radio networks and was expected to be a key player in the consolidation of the radio sector following the recent Communications Act, which paved the way for radio companies to merge.
Schoonmaker, an American who joined Emap in 1983, resigned from the company last week after heading what is now Emap's radio and digital television business, Emap Performance, for more than 10 years. The division contributed about 16% of turnover and 20% of group profits last year.
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