I suppose you are studying japanese and want to hear it spoken. It would not really make sense to put a tv channel online, however there are some things I know
If you need to study, NHK Radio online is really the way to go. I was drifting late last night (110+kph) on R-246 and listening to a great program on the difference between AKA-ONI and AO-ONI, red vs blue Japanese devils. I would have been damn proud to have used that NHK program in my Anthro grad school lectures.
There's also a weekly NHK TV propaganda program, "What's on Japan," which webcast in Japanese, English, etc.
Of the 11 Japanese channels, only http://www.lfx.jp/ has few mainstream FUJI TV offerings and the others are well, ummm, let's say Tokyo DV or Pongi TV is far, far better.... The National Institute of Polar Research(of Japan)Nime TV
PS: Back in the States, I just pay the extra $4.00/month to get the "foreign package" on Direct TV and watch FUJI and NTV channels 24/7 on the big screen. It's a hell of a lot better than fooling around with stoneage American broadband.