It is spring pledge drive time in the land of community radio: Resonance FM, WFMU, WBAI, WGXC, and many others have current campaigns to raise operating expenses. WBAI's situation is actually more drastic, as the New York City non-profit Pacifica radio station launched an emergency effort March 5 to raise a half a million dollars to stop the possible loss of its transmitter atop the Empire State Building. "The campaign titled 'The Transmitter Fund' aims to raise the funds needed to bring current the transmitter tower rent, which fell drastically behind in the aftermath of Hurricane Sandy," Pacifica's website says.