After a year, eBay closed down its Internet-based TV and radio ad selling platform, as cable channels avoided it due to fears of commoditizing ads.

If it’s ads for TV or radio you seek, you won’t find it on eBay. The passage of a year brought little business to eBay’s experimental e-Media Exchange, and the admarketpilot.com website associated with it vanished from the Internet.

AdWeek said the project never gathered support from the cable industry. Long accustomed to substantial ad revenue, they viewed eBay’s project as one that would undercut their margins.

“We have ended our pilot program in this market. We have been refocusing our resources on our core marketplace business and have determined that this initiative did not warrant continued time and attention,” eBay said in a statement to AdWeek.

eBay believes its program was misunderstood by potential participants. Instead of an auction, AdWeek noted the process would be initiated by a typical request for proposal (RFP), with responses and negotiations taking place. Older techies may see a resemblance here to the Electronic Data Interchange model used by government agencies and suppliers.

It’s difficult to see much success for eBay when it goes outside its core business. The Skype acquisition led to a monumental writeoff, its Kijiji marketplace trails Craigslist in classifieds, and now this latest setback.

Couple that with changes to the feedback system that have angered eBay sellers, along with policy shifts that favor volume sellers over the smaller individual sellers, and eBay seems to have a messy 2008 on its hands.