| Description: | This image shows the first Transient Buffer Board (TBB) data taken with LOFAR-CS1. Plotted in dark blue is about 1 ms worth of raw ADC data from one of the LOFAR dipoles and in light blue is the same data after the RFI from the short wave band and from the FM band has been filtered out. The oval, mouth-like shape is due to the ends being weighted down to improve the performance of the FFT, while the inner part (from about 0.25ms to 0.75ms) was not modified.
The most promising aspect is that the filtered dataset shows no special features, just thermal noise. This tells us that there is no pulsed RFI, no bit errors or holes in the data acquisition, no alignment errors of the memory blocks or other nasty things in the data. All these would show up as peaks or spikes in the filtered data, and would make our search for cosmic ray pulses so much harder.
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