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1) Cassini RPWS Key Parameter 60S maxmize
Resource ID:spase://VWO/NumericalData/Cassini/RPWS/KP_PT60S
Start:1997-10-25 00:00:00 Observatory:Cassini Cadence:60 seconds
Stop:2013-11-02 01:03:38 Instrument:Cassini RPWS Resource:NumericalData
The Cassini Radio and Plasma Wave Science (RPWS) calibrated summary key parameter data set includes reduced temporal and spectral resolution spectral information calibrated in units of spectral density for the entire Cassini mission. This data set includes calibrated values binned and averaged within 1 minute by 0.1 decade spectral channels for all times during the mission including the two Venus flybys, the Earth flyby, the Jupiter flyby, interplanetary cruise, and the entire Saturn tour. Data for this data set are acquired by the RPWS Low Frequency Receiver (LFR), Medium Frequency Receiver (MFR), and High Frequency Receiver (HFR). Data are presented in a set of fixed-record-length tables. This data set is intended to provide numerical summary data which can be used in conjunction with other Cassini fields and particles key parameter data sets to establish trends, select events, or simply as a browse data set for the Cassini RPWS archive. This data set should be among the first used by a user of any of the RPWS archive as it will lead one to information required to search for more detailed or highly specialized products.

2) Cassini RPWS Low Rate Full Resolution maxmize
Resource ID:spase://VWO/NumericalData/Cassini/RPWS/LRFULL_PT32S
Start:1997-10-25 00:00:00 Observatory:Cassini Cadence:32 seconds
Stop:2013-11-02 01:03:38 Instrument:Cassini RPWS Resource:NumericalData
The Cassini Radio and Plasma Wave Science (RPWS) Low Rate Full Resolution Calibrated (RPWS_LOW_RATE_FULL) is a data set including all spectral density measurements acquired by the RPWS in units of electric or magnetic field spectral density. This data set includes calibrated values for each frequency channel for each sensor for all times during the mission including the two Venus flybys, the Earth flyby, the Jupiter flyby, interplanetary cruise, and the entire Saturn tour. Data for this data set are acquired from the RPWS Low Frequency Receiver (LFR), Medium Frequency Receiver (MFR), Medium Frequency Digital Receiver (MFDR) (which can be used to replace MFR band 2 data) and High Frequency Receiver (HFR). Data are presented in a set of tables organized so as to have fixed-length records for ease in data handling. This data set is intended to be the most comprehensive and complete data set included in the Cassini RPWS archive. A browse data set is included with these data which provides for a graphical search of the data using a series of thumbnail and full-sized spectrograms which lead the user to the particular data file(s) of interest. This data set should be among the first used by a user of any of the RPWS archive as it will lead one to information required to search for more detailed or highly specialized products.

3) Galileo PWS Summary Electric Field Dataset maxmize
Resource ID:spase://VWO/NumericalData/Galileo/PWS/Summary.Electric
Start:1995-12-07 15:21:00 Observatory:Galileo Cadence:60 seconds
Stop:2003-09-21 18:45:00 Instrument:Galileo PWS Resource:NumericalData
This data set includes 1-minute averages of the electric and magnetic wave spectra obtained during the period that the Galileo plasma wave receiver was operated during the Jupiter orbital mission (prime, GEM and GMM). The parameter provided for the electric field spectrum is the electric field spectral density in units of V**2/m**2/Hz. The magnetic field spectrum is provided in units of magnetic field spectral density, nT**2/Hz. The spectral information is averaged and binned into 49 logarithmically-spaced channels from about 6 Hz to 5.6 MHz for the electric measurements and 34 channels from about 6 Hz to 75 kHz for the magnetic. Note that these 'channels' do not generally correspond to the 158 specific channels described in the instrument description document. The reduction in spectral resolution for this data set was performed in order to make the set more conducive to use as a browse data set. The sources of this browse data set are the High Frequency Receiver, Sweep Frequency Receiver, and Spectrum Analyzer which make up the Low Rate Science portion of the PWS.

4) Galileo PWS Summary Magnetic Field Dataset maxmize
Resource ID:spase://VWO/NumericalData/Galileo/PWS/Summary.Magnetic
Start:1995-12-07 15:21:00 Observatory:Galileo Cadence:60 seconds
Stop:2003-09-21 18:45:00 Instrument:Galileo PWS Resource:NumericalData
This data set includes 1-minute averages of the electric and magnetic wave spectra obtained during the period that the Galileo plasma wave receiver was operated during the Jupiter orbital mission (prime, GEM and GMM). The parameter provided for the electric field spectrum is the electric field spectral density in units of V**2/m**2/Hz. The magnetic field spectrum is provided in units of magnetic field spectral density, nT**2/Hz. The spectral information is averaged and binned into 49 logarithmically-spaced channels from about 6 Hz to 5.6 MHz for the electric measurements and 34 channels from about 6 Hz to 75 kHz for the magnetic. Note that these 'channels' do not generally correspond to the 158 specific channels described in the instrument description document. The reduction in spectral resolution for this data set was performed in order to make the set more conducive to use as a browse data set. The sources of this browse data set are the High Frequency Receiver, Sweep Frequency Receiver, and Spectrum Analyzer which make up the Low Rate Science portion of the PWS.

5) STEREO WAVES (SWAVES) PDF Dynamic Spectrogram Plots both Ahead and Behind s/c maxmize
Resource ID:spase://VWO/DisplayData/STEREO/SWAVES/DS.Color.PDF.P1D
Start:2006-10-27 20:24:42 Observatory:STEREO A Cadence:1 minute
Stop:2014-08-29 01:03:37 Instrument:STEREO-A Waves (SWAVES) Resource:DisplayData
This dataset contains 24 hour duration dynamic spectrogram plots from the combined STEREO A and B Waves instrument. The plots are provided in several file formats (PNG, Postscript and PDF) and there are renditions in color and grayscale with and without additional lines of time series data indicating the instrument operating status. These plots all reside within the same directory structure subdivided by year. The "new" subdirectory contain plots at a higher resolution but currently are not available for dates early in the mission. These data consist of output from the SWAVES HFR and LFR receivers. ? the High Frequency Receivers (HFR) - for spectral analysis and direction finding of radio noise generated from a few solar radii (16 MHz) to about half an Astronomical Unit (125 kHz) ? the Low Frequency Receiver (LFR) - for spectral analysis and direction finding from about half an Astronomical Unit (160 kHz) to one AU (2.5 kHz).

6) STEREO WAVES (SWAVES) Radio Intensity Spectra, both Ahead and Behind s/c maxmize
Resource ID:spase://VWO/NumericalData/STEREO/SWAVES/DS.Combined.PT1M
Start:2006-10-27 20:24:42 Observatory:STEREO A Cadence:1 minute
Stop:2014-08-29 01:03:39 Instrument:STEREO-A Waves (SWAVES) Resource:NumericalData
The CDF file contains 1 minute averaged radio intensity data from both the Ahead and Behind s/c. A description of the STEREO/WAVES instrument is provided in: Bougeret, J.L, et al. (2008), S/WAVES: The Radio and Plasma Wave Investigation on the STEREO Mission, Space Science Reviews, 136, 487-528. The STEREO / WAVES (SWAVES) instruments provide unique and critical observations for all primary science objectives of the STEREO mission, the generation of CMEs, their evolution, and their interaction with Earth's magnetosphere. SWAVES can probe a CME from lift-off to Earth by detecting the coronal and interplanetary (IP) shock of the most powerful CMEs, providing a radial profile through spectral imaging, determining the radial velocity from ~2 RS (from center of sun) to Earth, measuring the density of the volume of the heliosphere between the sun and Earth, and measuring important in situ properties of the IP shock, magnetic cloud, and density compression in the fast solar wind stream that follows. SWAVES measures the fluctuation electric field present on three orthogonal monopole antennas mounted on the back (anti-sunward) surface of the spacecraft. Each monopole antenna unit is a 6 m long Beryllium-Copper (BeCu) ?stacer? spring. The three units deploy from a common baseplate that also accommodates the preamplifier housing. The 6 m length was chosen to put the antenna quarter-wave resonance near the top of the SWAVES HFR2 frequency band. These data consist of output from the SWAVES HFR and LFR receivers. ? the High Frequency Receivers (HFR) - for spectral analysis and direction finding of radio noise generated from a few solar radii (16 MHz) to about half an Astronomical Unit (125 kHz) ? the Low Frequency Receiver (LFR) - for spectral analysis and direction finding from about half an Astronomical Unit (160 kHz) to one AU (2.5 kHz).

7) Ulysses URAP Daily Color Dynamic Spectrogram Plot maxmize
Resource ID:spase://VWO/DisplayData/Ulysses/URAP/DS.P1D
Start:1990-11-03 19:30:00 Observatory:Ulysses Cadence:128 seconds
Stop:2007-11-26 18:30:00 Instrument:Unified Radio and Plasma Waves (STO/URAP) Resource:DisplayData
from URAP Users Notes: Guide To The Archiving Of Ulysses Radio And Plasma Wave Data by Roger Hess, Robert MacDowall, Denise Lengyel-Frey March 15, 1995 - version 1.0 revised March 24, 1999 - version 1.1 revised June 8, 1999 - version 1.2 These color plots present URAP radio and plasma wave data in a format referred to as dynamic spectra. For the daily plots, the time resolution is 128 seconds, providing high-time resolution across the entire frequency range of the URAP receivers. The 10-day plots use 10-minute resolution data, which permits good detection of bursty wave activity. The 26-day plots use 1-hour resolution data; these plots correspond to the other Ulysses 26-day plot intervals, but the ability to identify wave activity is reduced. The power of the electric or magnetic field is shown in color as a 2-dimensional function of time and frequency. The plots include data from the URAP Radio Astronomy Receivers (RAR), Plasma Frequency Receiver (PFR), and Waveform Analyzer (WFA). Refer to the documentation for the 10-minute average archive data files, as well as Stone et al. (1992), for more general information on these instruments. Here, we describe the choices that were made in generating these plots. 1. Formats - These plots are available in 2 formats: GIF files for viewing with a web browser and Postscript files for high quality printed copies. The resolution of the GIF files is 776 x 600 pixels, a compromise between smaller size for network transfer and larger size for improved resolution. The Postscript files are sized to fit both 8.5x11 inch paper or A4 paper. The daily unzipped (zipped) Postscript files are typically 400-440 kB ( 130-140 KB) in size; the daily GIF files are typically 200-230 kB in size. (The 10-day and 26-day plots are similar in size.) 2. Data units - The data and the associated color bar are plotted in units of decibels, an old radio astronomer unit for describing signal to background ratio on a logarithmic scale. Specifically, Data_in_dB = 10. * log10(total power/background power) The data for electric field observations are in units of microvolts**2 Hz**(-1) as are the calculated background levels. The units for magnetic field observations (the bottom panels on the page) are nT**2 Hz**(-1). The data for the 1-day plots are comparable to the squared values of data in the URAP UFA 10-minute files. Although the ratio (total power-background power)/background power permits one to see weaker events in such plots, it is more sensitive to background determination and enhances the noise seen in the plots. Therefore, it is not used here. 3. Backgrounds - The background levels as a function of frequency for the RAR and WFA are determined from the data for the day, because they vary throughout the mission. The PFR background does not vary significantly with time, so fixed background levels are used. For each of the instruments, the backgrounds vary with the instrument mode, so separate sets of backgrounds are derived for each mode that is present. (Modes are discussed below). The PFR and WFA backgrounds also depend significantly on bit rate. For the RAR the background level selected is the lowest 3% of the data for each frequency; for the PFR and WFA, the background level selected is the lowest 10% of the data for each frequency. The higher number is chosen for the WFA because the data are substantially noisier than the RAR. It should be noted that this type of background subtraction will remove any signal at a given frequency that is constant throughout the day. An example is the quasithermal noise line ("plasma line") in the RAR data, when the density does not vary throughout the day. Note that for 10-day and 26-day plots, in particular, the background determination might result from a few hours of very low intensity data, which will cause all the other data, referenced to that background, to appear enhanced. This is an unfortunate consequence of determining the background levels from intervals of minimum data intensity. 4. Modes and other labels - Each of the instruments has several modes that affect the data display. The telemetry bit rate is also an important parameter. The key modes and the bit rate are shown on the dynamic spectrum as the thickness (or nonexistence) of a line. The RAR Hi and Lo bands are plotted in separate panels because they are commanded separately. For each band, the spin-plane and spin-axis antennas can be either summed or separate. If the RAR Hi or Lo band instrument is in summed mode, then a white line for the appropriate band is present under the RAR plot. Summed mode provides data used for 3-dimensional direction finding at the expense of a higher background level. Because the backgrounds will differ between summed and separate modes, backgrounds are calculated for both modes when they are present. Although the RAR is typically operated in a mode where measurements are made at all 76 frequencies, there are times when only a subset of the frequencies are sampled (called Measure mode). In these cases, the data plotted are interpolated in frequency to give a clearer picture of the events that might be taking place. These intervals are evident from the appearance of the data, which is smoothed in frequency; see Nov. 6, 1990, where the RAR Lo band is in Measure mode for the first 18 hours of the day. This example also shows the RAR hi band in a rarely-used, single frequency mode. If the Measure mode data occupy less than 10% of the day; they are not interpolated, because the events occurring at these times should be clear from the non-Measure mode data, and it is useful to see which frequencies are being sampled. The Jupiter flyby interval (e.g., Feb. 8, 1992) includes examples of short intervals of measure mode. The bit rate significantly affects the PFR and WFA backgrounds. If the science data bit rate is 1024 bps, it is indicated by a thick line, 512 bps is indicated by a thin line, and low ("emergency") bit rates, either 256 or 126 bps, by no line. The PFR operates in one of 3 modes - fast scan, slow scan, or fixed tune (see Stone et al., 1992). These 3 modes have different backgrounds and generate different interferences for the WFA instrument. Fast scan is shown by the white line under the PFR plot, slow scan is in progress if there is no line, and fixed tune is a single frequency mode (evident from the PFR data display), typically used in 1 hour/day intervals. The WFA instruments can sample either the electrical (E) antennas or the (B-field) search coil. For the low band of the WFA B field data (< 8 Hz), either By or Bz data are telemetered. The available parameter is shown by the white line above the B (WFA) plot (present=By, absent=Bz). 5. Interpolation - In addition to the interpolation discussed above for the RAR, the RAR data are interpolated to remove data gaps of 384 seconds or less. We interpolate the RAR data because the events observed in the RAR, such as solar type II and type III radio bursts, are mostly smoothly varying on time scales of a few minutes. Therefore, they are easier to visualize and interpret when data gaps are interpolated. For the events in the PFR and WFA data, predominantly bursty wave events, interpolation is not necessary and not performed. An exception occurs when the data telemetry rate is either 256 or 128 bps; then the WFA data are interpolated in time because they are not sampled every 128 sec. Finally, the RAR Hi band data, for which there are only 12 channels of data, are interpolated to fit a logarithmic frequency scale with 37 equivalent frequencies. 6. Interference and other issues affecting data interpretation - Each of these instruments, like all sensitive wave receivers, is affected by interference from other sources. For the RAR Hi band, an interference signal at 81 kHz is produced by the Ulysses GAS instrument. Depending on the mode in which the GAS instrument is operating, this interference can occur from 0 to 24 hours per day. If an algorithm determines that this interference is present in more than about 10% the RAR data for the day, we remove the 80 kHz data and interpolate from adjacent frequencies. The RAR Hi band also has an enhanced background at 120 kHz (source unknown). Subtraction of this enhanced background can cause artifacts in other events, like type III bursts. See Nov. 30, 1990 as an example. The RAR Lo band has an interference line at 8.75 kHz and odd harmonics caused by the Ulysses traveling wave tube amplifier (TWTA), which is part of the high gain telemetry system. In general, this signal is removed by the background subtraction, sometimes producing artifacts in weak radio events or the thermal noise spectrum at these frequencies The PFR experiences interference from the URAP Sounder; these data are removed from the plots and appear as short data gaps. The background levels of the PFR depend on bit rate, PFR mode, and the cadence of the URAP Fast Envelope Sampler (FES data not presented in these plots); these background variations can affect the appearance of events at the transition from one mode to another. The WFA data are affected by numerous interferences, of which the URAP PFR is the dominant source. WFA "backgrounds" vary significantly depending on whether the PFR is in fast or slow scan mode or fixed tune, so separate backgrounds are calculated for each of these. The URAP Sounder also causes interference; these data are removed from the plots and appear as short data gaps. Spacecraft thruster operations produce a variety of artifacts in the data; since we have no indication of these in our telemetry, they are not flagged on the plots. Examples may be seen on Feb 23, 1995 at 12:00 and on Feb. 25, 1995 at 15:00. An interesting "interference" is seen to disappear on Dec. 17, 1990; this is when the spacecraft nutation was stopped. This is best seen on the 26- day plots. To summarize, there are a variety of artifacts in the wave data that affect interpretation. These can result from corrupted telemetry values (producing bad pixels (most evident in the RAR plots, see March 23, 1993, from 6:00-14:00, or August 16, 1991, a very good example of very bad data quality), interferences (e.g., non-physical, block-like structures sometimes seen in the highest frequencies of the WFA E and B data (see March 14, 1995)), or changes of the instrument mode or the physical medium (e.g., a short interval of data with a very low signal level defines a background for the rest of the day that is not appropriate; see Nov. 4, 1990, when the Ex antenna was deployed). 7. Spacecraft location - At the lower left on the plots, 4 parameters related to the location of Ulysses at the mid-time of the plot are printed: a) the Ulysses-Sun (U-S) distance in AU, b) the heliographic latitude (Hlat_U) of Ulysses in degrees, c) the Ulysses-Sun-Earth (U-S-E) angle in degrees, and d) the Ulysses-Jupiter (U-J) distance in AU. These are among the most relevant parameters for interpreting the URAP data. Additional parameters, as well as a graphic showing the Ulysses location relative to the Sun, Earth, and Jupiter, can be found at the URAP Home Page at Goddard Space Flight Center (see below). 8. For additional information on these plots or on the URAP data, contact the PI of the URAP investigation, Dr. Robert MacDowall, at phone: 1-301-286-2608 fax: 1-301-286-1683 email: robert.macdowall@gsfc.nasa.gov. The URL for the URAP Home Page at Goddard Space Flight Center is http://urap.gsfc.nasa.gov/

8) Ulysses URAP RAR 144 Second Data in ASCII maxmize
Resource ID:spase://VWO/NumericalData/Ulysses/URAP/RAR.ASCII.PT144S
Start:1990-11-03 19:30:00 Observatory:Ulysses Cadence:144 seconds
Stop:2007-11-26 18:30:00 Instrument:Unified Radio and Plasma Waves (STO/URAP) Resource:NumericalData
This data set contains 144 second averages of the electric field intensities from the Ulysses Unified Radio and Plasma Wave Instrument Radio Astronomy Receiver (URAP/RAR). The following notes are taken from the Guide to Archiving of Ulysses URAP Data revised January 27, 2010 - version 1.3 ftp://ftp.rssd.esa.int/pub/ulysses/URAP/docs/others/archived_data_user_guide.html Appendix C: USER'S GUIDE TO RAR 144 SECOND AVERAGED DATA FILES The time period of 144 seconds was used for the averaging period because that is the basic cycling time of the instrument. The RAR continually cycles through a list of frequencies. There are 16 lists and the list currently in use is chosen by telecommand. The time period to complete the list is 144 seconds for the high band of the receiver (for telemetry bit rates of 1024 and 512 bps, the cycle time is 64 seconds for bit rates of 256 and 128 bps), after which the instrument begins with the list again. Therefore this period was chosen for the averaging period. The format of the data is indicated by the following Fortran statement which can be used to read the data: DIMENSION F(0:75) READ(1,'(I4,2I2,1X,3I2,1X,5I2,12(/6E12.4),/4E12.4)') + IYEAR, IMONTH, IDAY, IHOUR, IMINUTE, ISECOND, + LO_POL_MODE, LO_SUM_MODE, HI_POL_MODE, HI_SUM_MODE, + IBPS, F The variables are defined as follows: The date and time of the beginning of the averaging period are given in IYEAR, IMONTH, IDAY, IHOUR, IMINUTE, ISECOND. LO_POL_MODE and HI_POL_MODE are the polarization modes of the low and high receiver bands. Their values are defined as: 1: Polarization on. 2: Polarization off. 3: Polarization mode switched during the averaging interval. 4: Polarization mode was unknown (usually due to a data gap). LO_SUM_MODE and HI_SUM_MODE are the polarization modes of the low and high receiver bands. Their values are defined as: 1: Summation on. 2: Summation off. 3: Summation mode switched during the averaging interval. 4: Summation mode was unknown (usually due to a data gap). 1: Summation on. 2: Summation off. 3: Summation mode switched during the averaging interval. 4: Summation mode was unknown (usually due to a data gap). IBPS indicates the telemetry bit rate during the averaging interval. Its values are defined as: 1: 128 bps. 2: 256 bps. 3: 512 bps. 4: 1024 bps. 5: Bit rate changed during the averaging period. 6: Bit rate unknown - usually due to a data gap. F is a vector containing the average signal for the 76 frequencies of the low and high bands. Elements 0 through 63 are from the low band receiver and correspond to frequencies of 1.25+0.75*N Khz where N is the element number (0..63). The frequency channels from 64 to 75 correspond to the following frequencies: F(64): 52 KHz F(65): 63 KHz F(66): 71 KHz F(67): 100 KHz F(68): 120 KHz F(69): 148 KHz F(70): 196 KHz F(71): 272 KHz F(72): 387 KHz F(73): 540 KHz F(74): 740 KHz F(75): 940 KHz The units of the data are microvolt/Hz**.5 measured at the receiver input terminals. To convert to electric field strength the given data must be divided by the effective length of the antenna. This is complicated by the fact that the effective length depends on the antenna impedance which is affected by the plasma conditions local to the Ulysses spacecraft. The impedance will also depend on the frequency. In general, the RAR frequency channels that are well above the local electron plasma frequency are not affected by the plasma conditions and the effective length of 23 meters can be used. When the RAR is in summed, rather than separate, mode the determination of field strengths is even more difficult. Description of the Unified Radio and Plasma Wave Instrument Radio Astronomy Receiver The Radio Astronomy Receiver is divided into two parts, a low frequency receiver and a high frequency receiver. The low frequency receiver has 64 channels that cover the frequency range from 1.25 to 48.0 kHz in linear steps of 0.75 kHz. The high frequency receiver has 12 channels that cover the range from 52 kHz to 940 kHz in approximately logarithmic steps. The high frequency receiver is usually operated in what is called "measure" mode, which causes the receiver to step repeatedly through a list of frequencies that is determined by a ROM on board the spacecraft. There are 16 different lists and one of them is chosen by telecommand. The different lists emphasize different frequency ranges, so as to maximize the information received depending on the type of phenomena being studied. Some of the lists include all 12 possible frequency channels while other lists skip some of the frequencies. The list that has been used for most of the mission does include all frequecies, but there may be times when other lists have been used. At these times only a subset of the frequencies will be present. The low frequency receiver can be operated in measure mode (with its own set of lists of 8 or 16 frequencies) or in "linear sweep" mode where it steps through a contiguous set of frequencies. In linear mode, all 64 frequencies can be stepped through, or a subset of 32 frequencies can be chosen using the lower half, middle half, or upper half of the frequencies. For most of the mission, the low frequency receiver has been operated in linear mode with all 64 frequencies but there have been periods when it has operated in measure mode or in in linear mode with less than 64 frequencies. During these periods only a subset (8, 16, or 32) of the 64 possible frequencies will appear. Besides the intensity of a signal reaching the spacecraft, the RAR can also, when operated in particular modes, determine additional information about the source of the radiation, including its direction relative to the location of Ulysses, its angular size, and its polarization. This is most efficiently done with the signal from the X and Z axis antennas summed together electronically either with or without a phase shift added between the two signals. Although this additional information cannot be recovered from the averaged data, the mode does have a large effect on the background signal level, so the mode of high and low frequency receivers is given in the data as either summed (X and Z antenna combined) or separate (X antenna alone). Reference: Astron. Astrophys. Suppl. Ser., 92(2), 291-316 (1992).

9) Ulysses URAP RAR 144 Second Data maxmize
Resource ID:spase://VWO/NumericalData/Ulysses/URAP/RAR.CDF.PT144S
Start:1990-11-03 19:30:00 Observatory:Ulysses Cadence:144 seconds
Stop:2007-11-26 18:30:00 Instrument:Unified Radio and Plasma Waves (STO/URAP) Resource:NumericalData
This data set contains 144 second averages of the electric field intensities from the Unified Radio and Plasma Wave Instrument Radio Astronomy Receiver. Units are microVolt/Hz**0.5 measured at the receiver input terminals. To convert to electric field strength the given data must be divided by the effective length of the antenna. This is complicated by the fact that the effective length depends on the antenna impedance which is affected by the plasma conditions local to the Ulysses spacecraft. The impedance will also depend on the frequency. In general, the RAR frequency channels that are well above the local electron plasma frequency are not affected by the plasma conditions and the effective length of 23 meters can be used. When the RAR is in summed, rather than separate, mode the determination of field strengths is even more difficult. The time period of 144 seconds was used for the averaging period because that is the basic cycling time of the instrument. The RAR continually cycles through a list of frequencies. There are 16 lists and the list currently in use is chosen by telecommand. The time period to complete the list is 144 seconds for the high band of the receiver (for telemetry bit rates of 1024 and 512 bps, the cycle time is 64 seconds for bit rates of 256 and 128 bps), after which the instrument begins with the list again. Therefore this period was chosen for the averaging period. Notes on the Radio Astronomy Receiver from URAP User Notes http://helio.esa.int/ulysses/archive/urap_un.html The Radio Astronomy Receiver is divided into two parts, a low frequency receiver and a high frequency receiver. The low frequency receiver has 64 channels that cover the frequency range from 1.25 to 48.0 kHz in linear steps of 0.75 kHz. The high frequency receiver has 12 channels that cover the range from 52 kHz to 940 kHz in approximately logarithmic steps. The high frequency receiver is usually operated in what is called "measure" mode, which causes the receiver to step repeatedly through a list of frequencies that is determined by a ROM on board the spacecraft. There are 16 different lists and one of them is chosen by telecommand. The different lists emphasize different frequency ranges, so as to maximize the information received depending on the type of phenomena being studied. Some of the lists include all 12 possible frequency channels while other lists skip some of the frequencies. The list that has been used for most of the mission does include all frequecies, but there may be times when other lists have been used. At these times only a subset of the frequencies will be present. The low frequency receiver can be operated in measure mode (with its own set of lists of 8 or 16 frequencies) or in "linear sweep" mode where it steps through a contiguous set of frequencies. In linear mode, all 64 frequencies can be stepped through, or a subset of 32 frequencies can be chosen using the lower half, middle half, or upper half of the frequencies. For most of the mission, the low frequency receiver has been operated in linear mode with all 64 frequencies but there have been periods when it has operated in measure mode or in in linear mode with less than 64 frequencies. During these periods only a subset (8, 16, or 32) of the 64 possible frequencies will appear. Besides the intensity of a signal reaching the spacecraft, the RAR can also, when operated in particular modes, determine additional information about the source of the radiation, including its direction relative to the location of Ulysses, its angular size, and its polarization. This is most efficiently done with the signal from the X and Z axis antennas summed together electronically either with or without a phase shift added between the two signals. Although this additional information cannot be recovered from the averaged data, the mode does have a large effect on the background signal level, so the mode of high and low frequency receivers is given in the data as either summed (X and Z antenna combined) or separate (X antenna alone). Reference: Astron. Astrophys. Suppl. Ser., 92(2), 291-316 (1992).

10) Spectrograms of Voyager 1 PRA Highband Receiver Jupiter encounter, 48 sec resolution maxmize
Resource ID:spase://VWO/DisplayData/Voyager1/PRA/Jupiter/High.P1D
Start:1979-02-01 00:00:00 Observatory:Voyager 1 Cadence:48 seconds
Stop:1979-04-13 23:59:59 Instrument:Voyager 1 Planetary Radio Astronomy (PRA) experiment Resource:DisplayData
Spectrogram plots in GIF format derived from Voyager 1 Planetary Radio Astronomy (PRA) Highband receiver daily files during Jupiter Encounter (1979-02-01 to 1979-04-13). These plots are available for both polarization channels. The color scale of these plots represent the electric field power spectral density in units of millibels. Across the top of each spectrogram in the spacecraft and instrument name, the name of the binary data file that was used to create this plot, the polarization channel (Left or Right) and the date in the format YYMMDD. The data set provides 48 second resolution highband radio mean power data in units of millibels. The high-band receiver consisted of 128 channels of 200 kHz bandwidth each, with center frequencies spaced at 307.2 kHz intervals from 1.2 MHz to 40.4 MHz. The highband receiver was designed especially for the observation of Jovian decametric radio emissions. The PRA radiometer was usually operated routinely in the so-called POLLO sweeping mode, in which all 198 frequency channels of the high- and low-band receivers together were swept in 6 sec, dwelling at each channel for 25 msec. From one step to the next in the channel switching sequence, the antenna polarization sense was reversed, i.e., was changed from RH to LH or vice versa. Thus the time required for making a measurement of both the RH and LH intensity components at both senses of elliptical polarization at a given frequency was 12 sec. The data consists of successive averages of 4 pairs of RH and LH intensity measurements, each average spanning an interval of 48 sec. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. Note: The polarization indicated is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein.

11) Voyager 1 PRA Highband Receiver Jupiter encounter, 48 sec resolution maxmize
Resource ID:spase://VWO/NumericalData/Voyager1/PRA/Jupiter/High.PT48S
Start:1979-02-01 00:00:00 Observatory:Voyager 1 Cadence:48 seconds
Stop:1979-04-13 23:59:59 Instrument:Voyager 1 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
Voyager 1 Planetary Radio Astronomy (PRA) Highband receiver daily files during Jupiter Encounter (1979-02-01 to 1979-04-13). Associated with these binary data are a series of quick-look GIF plots created using the binary data. The plots are available for both polarization channels. The data set provides 48 second resolution highband radio mean power data in units of millibels. The high-band receiver consisted of 128 channels of 200 kHz bandwidth each, with center frequencies spaced at 307.2 kHz intervals from 1.2 MHz to 40.4 MHz. The highband receiver was designed especially for the observation of Jovian decametric radio emissions. The PRA radiometer was usually operated routinely in the so-called POLLO sweeping mode, in which all 198 frequency channels of the high- and low-band receivers together were swept in 6 sec, dwelling at each channel for 25 msec. From one step to the next in the channel switching sequence, the antenna polarization sense was reversed, i.e., was changed from RH to LH or vice versa. Thus the time required for making a measurement of both the RH and LH intensity components at both senses of elliptical polarization at a given frequency was 12 sec. The data consists of successive averages of 4 pairs of RH and LH intensity measurements, each average spanning an interval of 48 sec. The format of these binary data files is as follows: file separation variable year, month, day information millisecond decimal value of the day Integer array (128,2) for 128 left and right channels (NOTE 128 channels for Hi-band; 70 channels for Lo-band) file separation variable There is an IDL program that reads these files into an IDL-format save set. See Information URL for a link to this file. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. Note: The polarization indicated is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein.

12) Voyager 1 PRA Lowband Receiver Jupiter encounter, 6 sec resolution maxmize
Resource ID:spase://VWO/NumericalData/Voyager1/PRA/Jupiter/Low.PT6S
Start:1979-01-06 00:00:34 Observatory:Voyager 1 Cadence:6 seconds
Stop:1979-04-13 23:59:08 Instrument:Voyager 1 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
(Description based on material from VG1_PRA_JUP_HRES_DS.CAT) Voyager 1 Radio Astronomy (PRA) data from the Jupiter encounter (1979-01-06 to 1979-04-13). The data set provides 6 second high resolution lowband radio mean power data. The data are provided for 70 instrument channels, covering 1.2 to 1326.0 kHz. This data set (VG1-J-PRA-3-RDR-LOWBAND-6SEC-V1.0) contains data acquired by the Voyager-1 Planetary Radio Astronomy (PRA) instrument during the Jupiter encounter. The bounding time interval set for most Voyager 1 Jupiter PDS data sets is the Voyager project defined 'far encounter' mission phase boundary (1979-02-28 to 1979-03-22). Since, however, the PRA instrument is able to observe planetary phenomenon at much larger ranges than other fields and particles experiments, this boundary is artificial with respect to PRA. Hence, PRA lowband data provided here cover the entire Jupiter Encounter Phase (1979-01-06 to 1979-04-13). Data from beyond the far encounter interval is contained in the cruise data archive which is available from the NSSDC. VG1-J-PRA-3-RDR-LOWBAND-6SEC-V1.0 contains data at the highest time resolution possible during normal operations. The normal mode of PRA operations during the planetary encounters was to sweep through the two radio receiver bands, high band (40.5 to 1.5 MHz in 128 channels spaced 0.3072 MHz apart) and low band (1326.0 to 1.2 kHz in 70 channels spaced 19.2 kHz apart) in a period of 6 seconds. The receivers measured, on alternate samples, the left hand circular and right hand circular (radio definition) power. Measured Parameters =================== The data here are from the low frequency receiver band and are 'packaged' into spacecraft major frame records. Each major frame is 48 seconds long or eight sweeps through the PRA receiver. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. The data format is ASCII and consists of a time indicator followed by an array containing the eight low band sweeps. Time is spacecraft event time (SCET) which is basically universal time at the spacecraft. Specifically, time is in the form of YYMMDD and seconds into YYMMDD. Both are written as I6. Example: July 1, 1979 at 12 hours SCET would be 790701, 43200. The seconds correspond, to the nearest second, to the start of the sweep (which occurs in PRA high band). The first value in low band (1326.0 kHz) occurs some 3.9 seconds after this time and samples at successively lower frequencies are spaced 0.03 seconds apart. Only one time is given for the entire major frame, thus the start of each sweep is the time given plus 6 times the sweep number minus 1 (i.e., 0 through 7). The data array is dimensioned as 71 X 8 and written as I4 format (i.e. 568I4). The '8' corresponds to the eight PRA sweeps. The lowest 68 of the 70 low band channels (1287.6 to 1.2 kHz) are in positions 2-69. Positions 70-71 should be ignored. Missing or bad data values are set to zero. In position 1 of each sweep is a status word where the 12 least significant bits have used, although not all 12 have meaning for PRA low band. Numbering those bits 0 for least significant to 11 for most significant, the bits that have meaning are as follows: bit 0: 15 dB attenuator in use when equal to 1 1: 30 dB attenuator in use when equal to 1 2: 45 dB attenuator in use when equal to 1 9,10 (together): polarization of first channel sampled (1326.0 kHz) according to the scheme: +---------------------------+ | | |value bit| | | | 10= | | | | 0 | 1 | |value bit 9=| 0 | R | L | | | 1 | L | R | +---------------------------+ Polarization at successively lower frequencies is opposite to the frequency above it, i.e. either a LRLR or an RLRL pattern. Successive 6-second sweeps start on the opposite polarization as the previous sweep as indicated in the status bits. Note that this polarization is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein. Missing or bad data values are set to zero. If the status word is zero, any data in that receiver sweep should be discarded. Data Coverage ============= The data are stored as 4 ASCII tables (.TAB), each accompanied with a PDS label file (.LBL) which describes properties of the data file. Data cover the following time intervals: Volume ID: VGPR_1201 +------------------------------------------------------------------------+ | Filename |Records| Start | Stop | |------------------------------------------------------------------------| | PRA_I.TAB | 35569| 1979-01-06T00:00:34.000Z | 1979-01-30T23:59:47.000Z| | PRA_II.TAB| 39493| 1979-01-31T00:00:35.000Z | 1979-02-25T23:59:47.000Z| |PRA_III.TAB| 41371| 1979-02-26T00:00:35.000Z | 1979-03-22T23:59:56.000Z| | PRA_IV.TAB| 24587| 1979-03-23T00:00:44.000Z | 1979-04-13T23:59:08.000Z| +------------------------------------------------------------------------+ Confidence Level Overview ========================= The accuracy of calibration in the PRA low band is approximately 2 dB, except at frequencies below 100 kHz where it is somewhat worse. Interference from the Voyager power subsystem is a major problem to the PRA instrument, affecting many of the 70 low band channels. This interference manifests itself by abrupt changes in background levels. Some channels, notably 136 and 193 kHz, are almost always affected, whereas, others are only affected for short intervals. Usually, this interference is only a problem when the natural signals are weak. Additional information associated with this data set is available in the following files: +-----------------------------------------------------------------------------------------------------------------------------------+ | file | contents | | http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/VG1_PRA1_INST.CAT |VG1 PRA instrument description | | http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/VG1_PRA_JUP_HRES_DS.CAT | data set description | | http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/PERSON.CAT | personnel information | | http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/REF.CAT |key reference description | | http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/DOCUMENT/INSTRUMENT |ASCII and HTML versions of the PRA| | |investigation description paper | +-----------------------------------------------------------------------------------------------------------------------------------+

13) Spectrograms of Voyager 2 PRA Highband Receiver Jupiter encounter, 48 sec resolution maxmize
Resource ID:spase://VWO/DisplayData/Voyager2/PRA/Jupiter/High.P1D
Start:1979-06-01 00:00:34 Observatory:Voyager 2 Cadence:48 seconds
Stop:1979-07-30 23:59:59 Instrument:Voyager 2 Planetary Radio Astronomy (PRA) experiment Resource:DisplayData
Spectrogram plots in GIF format derived from Voyager 2 Planetary Radio Astronomy (PRA) Highband receiver daily files during Jupiter Encounter (1979-06-01 to 1979-07-30). These plots are available for both polarization channels. The color scale of these plots represent the electric field power spectral density in units of millibels. Across the top of each spectrogram in the spacecraft and instrument name, the name of the binary data file that was used to create this plot, the polarization channel (Left or Right) and the date in the format YYMMDD. The data set provides 48 second resolution highband radio mean power data in units of millibels. The high-band receiver consisted of 128 channels of 200 kHz bandwidth each, with center frequencies spaced at 307.2 kHz intervals from 1.2 MHz to 40.4 MHz. The highband receiver was designed especially for the observation of Jovian decametric radio emissions. The PRA radiometer was usually operated routinely in the so-called POLLO sweeping mode, in which all 198 frequency channels of the high- and low-band receivers together were swept in 6 sec, dwelling at each channel for 25 msec. From one step to the next in the channel switching sequence, the antenna polarization sense was reversed, i.e., was changed from RH to LH or vice versa. Thus the time required for making a measurement of both the RH and LH intensity components at both senses of elliptical polarization at a given frequency was 12 sec. The data consists of successive averages of 4 pairs of RH and LH intensity measurements, each average spanning an interval of 48 sec. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. Note: The polarization indicated is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein.

14) Voyager 2 PRA Highband Receiver Jupiter encounter, 48 sec resolution maxmize
Resource ID:spase://VWO/NumericalData/Voyager2/PRA/Jupiter/High.PT48S
Start:1979-06-01 00:00:34 Observatory:Voyager 2 Cadence:48 seconds
Stop:1979-07-30 23:59:59 Instrument:Voyager 2 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
Voyager 2 Planetary Radio Astronomy (PRA) Highband receiver daily files during Jupiter Encounter (1979-06-01 to 1979-07-30). Associated with these binary data are a series of quick-look GIF plots created using the binary data. The plots are available for both polarization channels. The data set provides 48 second resolution highband radio mean power data in units of millibels. The high-band receiver consisted of 128 channels of 200 kHz bandwidth each, with center frequencies spaced at 307.2 kHz intervals from 1.2 MHz to 40.4 MHz. The highband receiver was designed especially for the observation of Jovian decametric radio emissions. The PRA radiometer was usually operated routinely in the so-called POLLO sweeping mode, in which all 198 frequency channels of the high- and low-band receivers together were swept in 6 sec, dwelling at each channel for 25 msec. From one step to the next in the channel switching sequence, the antenna polarization sense was reversed, i.e., was changed from RH to LH or vice versa. Thus the time required for making a measurement of both the RH and LH intensity components at both senses of elliptical polarization at a given frequency was 12 sec. The data consists of successive averages of 4 pairs of RH and LH intensity measurements, each average spanning an interval of 48 sec. The format of these binary data files is as follows: file separation variable year, month, day information millisecond decimal value of the day Integer array (128,2) for 128 left and right channels (NOTE 128 channels for Hi-band; 70 channels for Lo-band) file separation variable There is an IDL program that reads these files into an IDL-format save set. See Information URL for a link to this file. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. Note: The polarization indicated is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein.

15) Voyager 2 PRA Lowband Receiver Jupiter encounter, 6 sec resolution maxmize
Resource ID:spase://VWO/NumericalData/Voyager2/PRA/Jupiter/Low.PT6S
Start:1979-04-25 00:04:00 Observatory:Voyager 2 Cadence:6 seconds
Stop:1979-08-04 23:05:33 Instrument:Voyager 2 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
(Description based on material from VG2_PRA_JUP_HRES_DS.CAT) Voyager 2 Radio Astronomy (PRA) data from the Jupiter encounter (1979-04-25 to 1979-08-04). The data set provides 6 second high resolution lowband radio mean power data. The data are provided for 70 instrument channels, covering 1.2 to 1326.0 kHz. This data set (VG2-J-PRA-3-RDR-LOWBAND-6SEC-V1.0) contains data acquired by the Voyager-2 Planetary Radio Astronomy (PRA) instrument during the Jupiter encounter. The bounding time interval set for most Voyager 2 Jupiter PDS data sets is the Voyager project defined 'far encounter' mission phase boundary (1979-07-02 to 1979-08-03). Since, however, the PRA instrument is able to observe planetary phenomenon at much larger ranges than other fields and particles experiments, this boundary is artificial with respect to PRA. Hence, PRA lowband data provided here cover the entire Jupiter Encounter Phase (1979-04-25 to 1979-08-04). Data from beyond the far encounter interval is contained in the cruise data archive which is available from the NSSDC. VG2-J-PRA-3-RDR-LOWBAND-6SEC-V1.0 contains data at the highest time resolution possible during normal operations. The normal mode of PRA operations during the planetary encounters was to sweep through the two radio receiver bands, high band (40.5 to 1.5 MHz in 128 channels spaced 0.3072 MHz apart) and low band (1326.0 to 1.2 kHz in 70 channels spaced 19.2 kHz apart) in a period of 6 seconds. The receivers measured, on alternate samples, the left hand circular and right hand circular (radio definition) power. Measured Parameters =================== The data here are from the low frequency receiver band and are 'packaged' into spacecraft major frame records. Each major frame is 48 seconds long or eight sweeps through the PRA receiver. The data are calibrated and are given in units of 'millibels' which is 1000 times the log of the received power. Zero millbels corresponds to approximately 1.4 x 10^-21 W m^-2 Hz^-1, however, this value is never seen in practice. The minimum values detected, which includes receiver internal and spacecraft generated noise, are about 2300 to 2400 millibels, or about 3.5 x 10^-19 W m^-2 Hz^-1; even higher values are seen at the very lowest frequencies. The data format is ASCII and consists of a time indicator followed by an array containing the eight low band sweeps. Time is spacecraft event time (SCET) which is basically universal time at the spacecraft. Specifically, time is in the form of YYMMDD and seconds into YYMMDD. Both are written as I6. Example: July 1, 1979 at 12 hours SCET would be 790701, 43200. The seconds correspond, to the nearest second, to the start of the sweep (which occurs in PRA high band). The first value in low band (1326.0 kHz) occurs some 3.9 seconds after this time and samples at successively lower frequencies are spaced 0.03 seconds apart. Only one time is given for the entire major frame, thus the start of each sweep is the time given plus 6 times the sweep number minus 1 (i.e., 0 through 7). The data array is dimensioned as 71 X 8 and written as I4 format (i.e. 568I4). The '8' corresponds to the eight PRA sweeps. The lowest 68 of the 70 low band channels (1287.6 to 1.2 kHz) are in positions 2-69. Positions 70-71 should be ignored. Missing or bad data values are set to zero. In position 1 of each sweep is a status word where the 12 least significant bits have used, although not all 12 have meaning for PRA low band. Numbering those bits 0 for least significant to 11 for most significant, the bits that have meaning are as follows: bit 0: 15 dB attenuator in use when equal to 1 1: 30 dB attenuator in use when equal to 1 2: 45 dB attenuator in use when equal to 1 9,10 (together): polarization of first channel sampled (1326.0 kHz) according to the scheme: +---------------------------+ | | |value bit| | | | 10= | | | | 0 | 1 | |value bit 9=| 0 | R | L | | | 1 | L | R | +---------------------------+ Polarization at successively lower frequencies is opposite to the frequency above it, i.e. either a LRLR or an RLRL pattern. Successive 6-second sweeps start on the opposite polarization as the previous sweep as indicated in the status bits. Note that this polarization is the received polarization, not necessarily the emitted polarization. Correct interpretation of the received polarization depends on the antenna plane orientation relative to the radio source. A good description of this concept can be found in Leblanc Y., Aubier M. G., Ortega-Molina A., Lecacheux A., 1987, J.Geophys. Res. 92, 15125 and in Wang, L. and Carr, T.D., Recalibration of the Voyager PRA antenna for polarization sense measurement, Astron. Astrophys., 281, 945-954, 1994. and references therein. Missing or bad data values are set to zero. If the status word is zero, any data in that receiver sweep should be discarded. Data Coverage ============= The data are stored as 4 ASCII tables (.TAB), each accompanied with a PDS label file (.LBL) which describes properties of the data file. Data cover the following time intervals: Volume ID: VGPR_1201 +------------------------------------------------------------------------+ | Filename |Records| Start | Stop | |------------------------------------------------------------------------| | PRA_I.TAB | 32707| 1979-04-25T00:00:04.000Z |1979-05-28T23:59:14.000Z | | PRA_II.TAB| 34207| 1979-05-29T00:00:02.000Z |1979-06-23T23:59:59.000Z | |PRA_III.TAB| 31652| 1979-06-24T00:00:47.000Z |1979-07-12T23:59:58.000Z | | PRA_IV.TAB| 34416| 1979-07-13T00:00:46.000Z |1979-08-04T23:05:33.000Z | +------------------------------------------------------------------------+ Confidence Level Overview ========================= The accuracy of calibration in the PRA low band is approximately 2 dB, except at frequencies below 100 kHz where it is somewhat worse. Interference from the Voyager power subsystem is a major problem to the PRA instrument, affecting many of the 70 low band channels. This interference manifests itself by abrupt changes in background levels. Some channels, notably 136 and 193 kHz, are almost always affected, whereas, others are only affected for short intervals. Usually, this interference is only a problem when the natural signals are weak. Additional information associated with this data set is available in the following files: +-----------------------------------------------------------------------------------------------------------------------------------+ | file | contents | |------------------------------------------------------------------------------------------------|----------------------------------| |http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/VG2_PRA_INST.CAT | VG1 PRA instrument description | |http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/VG2_PRA_JUP_HRES_DS.CAT | data set description | |http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/PERSON.CAT |personnel information | |http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/CATALOG/REF.CAT |key reference description | |http://ppi.pds.nasa.gov/ditdos/download?id=pds://PPI/VGPR_1201/DOCUMENT/INSTRUMENT |ASCII and HTML versions of the PRA| | |investigation description paper | +-----------------------------------------------------------------------------------------------------------------------------------+

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