Below are two examples of graphs that have narrowband interference. This form of RFI is usually generated by television, radio, and satellite transmitters. Note that the signal is more or less constant, lasting the entire 107 seconds of the data. Also note that the signal is so strong that it "drives" all the other signals way down (since the SETI@home screensaver normalizes the graph).
©2017 University of California
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.