Broadcasting & Cable is reporting that Democratic Michigan Rep. John Dingell has sent the FCC commissioners letters asking for clarification of the National Broadband Plan with respect to several issues, including public broadcasting. The former House Energy and Commerce Committee chair wants to know if spectrum give-back will remain voluntary even if the goal of 120 MHz is not achieved; if the FCC would involuntarily reallocate noncom spectrum from stations decline to participate (Current, Feb. 8, 2010); and if the FCC have to propose amendments to the Public Broadcasting Act. In the letters Dingell said he would like answers by April 16.