Community based radio stations is a common choice for radio when it comes to Japan music and FM Chappy is popular in that case. FM Chappy has been known for their popular talk shows, community related radio programs and some cool Japanese music. So it can be said that they are a well balanced radio station of Japan.
FM Chappy official website address is www.fmchappy.jp
If the Radio is extremely choppy and stops every 5 seconds, try listen to this Radio at different time.
Not all Radio Stations function for 24 hours everyday. If you can't listen to any Radio, try to listen at different time, as the Radio Station may stop during midnight according to its own country time zone.