PSP FIELDS Digital Fields Board, DFB, dV12 data:\n\nThe DFB is the low frequency, less than 75 kHz, component of the FIELDS experiment on the Parker Solar Probe spacecraft, see reference [1] below. For a full description of the FIELDS experiment, see reference [2]. For a description of the DFB, see reference [3].\n\nDFB AC bandpass data consist of peak and average values of the absolute value of bandpassed time series waveform data over a time interval equal to the reporting cadence. The AC bandpass data have the peak response frequency of each bin reported in the metadata. The frequency response curves for these bins are given in [3].\n\nThe Level 2 data products contained in this data file have been calibrated for:\n\n 1) The ~6.3 dB loss associated with forming the bandpass signal, see reference [3]\n 2) DFB in-band gain\n 3) The search coil preamplifier response, when applicable\n\nCalibrations for the DFB digital filter gains and analog filter gains have not been implemented as it was determined that these could not be applied accurately to single numerical values representing a broadband signal response and because all bins except the highest frequency bin have a flat gain response equal to one due to these filters. Calibrations for the FIELDS preamplifiers have not been implemented as the preamplifier response is flat and equal to one through the DFB frequency range. Corrections for plasma sheath impedance gain and antenna effective length have not been applied to voltage sensor signals. These corrections will be applied in the Level 3 DFB data products. Therefore, all voltage sensor quantities when present in these Level 2 data products are expressed by using units of Volts. Likewise, all magnetic field quantities when present in these Level 2 data products are expressed by using units of nanoTelsas.\n\nThe Level 2 data products contained in this data file are expressed in sensor coordinates: e.g. dV12, dV34 for voltage measurements and [u,v,w] for the searchcoil magnetometer.\n\nThe time resolution of the DFB AC bandpass filtered data can vary by multiples of 2^N. During encounter when PSP is within 0.25 AU of the Sun, the DFB AC bandpass filtered data cadence is typically 1/8 of a NYsecond [2]. Timestamps correspond to the center time of each window.\n\nReferences:\n\n 1) Fox, N.J., Velli, M.C., Bale, S.D. et al., Space Sci Rev (2016) 204:7. https://doi.org/10.1007/s1121401502116\n 2) Bale, S.D., Goetz, K., Harvey, P.R. et al., Space Sci Rev (2016) 204:49. https://doi.org/10.1007/s1121401602445\n 3) Malaspina, D.M., Ergun, R.E., Bolton, M. et al., JGR Space Physics (2016), 121, 5088-5096. https://doi.org/10.1002/2016JA022344