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1) 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.

2) 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.

3) 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 | +-----------------------------------------------------------------------------------------------------------------------------------+

4) VG1 JUP PRA RESAMPLED SUMMARY BROWSE 48SEC V1.0 maxmize
Resource ID:spase://VMO/NumericalData/Voyager1/PRA/Jupiter/PT48S
Start:1979-01-06 00:00:48 Observatory:Voyager 1 Cadence:48 seconds
Stop:1979-04-13 23:58:24 Instrument:Voyager 1 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
Data Set Overview ================= Instrument P.I. : James W. Warwick Data Supplier : Michael L. Kaiser Data sampling rate : 48 seconds Data Set Start Time : 1979-01-06T00:00:48.000Z Data Set Stop Time : 1979-04-13T23:58:24.000Z This data set consists of edited browse data derived from an original data set obtained from the Voyager 1 Planetary Radio Astronomy (PRA) instrument in the vicinity of Jupiter. Data are provided for 70 instrument channels covering the range from 1.2 kHz to 1326 kHz in uniform 19.2 kHz steps, each 1 kHz wide. Data are included for the period 1979-01-06 00:00:48 through 1979-04-13 23:58:24. In order to produce this data set from the original raw PRA data, several steps have been taken: 1. The PRA operates in a variety of modes; data from modes in which the receiver does not scan rapidly through its frequency range have been removed; 2. The data have been calibrated as best we know how; 3. The data have been split into Left Hand Circular (LHC) and Right Hand Circular (RHC) components; 4. The data have been binned into 48-second intervals. Thus, values at a given channel are separated in time by an increment of 48 seconds; each 48-second time interval has associated with it a value for LHC polarization and one for RHC polarization. During data gaps, the entire record is absent from the data set; that is, missing records have not been zero-filled or otherwise marked. Bad data within a record is indicated by the value zero, which cannot otherwise occur. Each datum is returned as a 16-bit quantity; it represents the mean power received in the given channel at the specified time and polarization. The returned quantity is the value in mB about a reference flux density. To convert a returned quantity to flux, use the formula: flux = 7.0x10^(-22)x10^(mB/1000) W m-2 Hz-1 Parameters ========== Data Set Parameter 'RADIO WAVE SPECTRUM' ---------------------------------------- Data Set Parameter Name : RADIO WAVE SPECTRUM Data Set Parameter Unit : MILLIBEL Sampling Parameter Name : TIME Sampling Parameter Unit : SECOND Sampling Parameter Resolution : 0.001 Sampling Parameter Interval : 48 Minimum Available Sampling Int : 12 Noise Level : 2400 A set of derived parameters consisting of power fluxes at various contiguous frequencies over a range of frequencies. Millibels may be converted to watts/m**2/Hz by using the formula for flux indicated above. Source Instrument Parameters ============================ Instrument Host ID : VG1 Data Set Parameter Name : RADIO WAVE SPECTRUM Instrument Parameter Name : WAVE FLUX DENSITY ELECTRIC FIELD WAVEFORM ELECTRIC FIELD COMPONENT MAGNETIC FIELD COMPONENT WAVE ELECTRIC FIELD INTENSITY WAVE MAGNETIC FIELD INTENSITY Important Instrument Parameters : 1 (for all parameters) Data Coverage ============= Filename Records Start Stop ------------------------------------------------------------------- T790106 1565 1979-01-06T00:00:48.000Z 1979-01-06T23:59:12.000Z T790107 1430 1979-01-07T00:01:36.000Z 1979-01-07T23:59:12.000Z T790108 1454 1979-01-08T00:01:36.000Z 1979-01-08T23:59:12.000Z T790109 1518 1979-01-09T00:01:36.000Z 1979-01-09T23:59:12.000Z T790110 1517 1979-01-10T00:01:36.000Z 1979-01-10T23:59:12.000Z T790111 1522 1979-01-11T00:01:36.000Z 1979-01-11T23:59:12.000Z T790112 1460 1979-01-12T00:01:36.000Z 1979-01-12T23:25:36.000Z T790113 298 1979-01-13T07:27:12.000Z 1979-01-13T23:58:24.000Z T790114 1460 1979-01-14T00:00:48.000Z 1979-01-14T23:59:12.000Z T790115 1535 1979-01-15T00:01:36.000Z 1979-01-15T23:59:12.000Z T790116 1424 1979-01-16T00:01:36.000Z 1979-01-16T23:59:12.000Z T790117 1442 1979-01-17T00:01:36.000Z 1979-01-17T23:59:12.000Z T790118 1440 1979-01-18T00:01:36.000Z 1979-01-18T23:59:12.000Z T790119 1371 1979-01-19T00:01:36.000Z 1979-01-19T23:59:12.000Z T790120 1396 1979-01-20T00:01:36.000Z 1979-01-20T23:59:12.000Z T790121 1540 1979-01-21T00:01:36.000Z 1979-01-21T23:58:24.000Z T790122 1551 1979-01-22T00:00:48.000Z 1979-01-22T23:59:12.000Z T790123 10

5) VG1 JUP PRA CALIBRATED HI-RES LOW FREQ. REC. BAND DATA V1.0 maxmize
Resource ID:spase://VMO/NumericalData/Voyager1/PRA/Jupiter/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
Data Set Overview ================= 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 [LEBLANCETAL1987]. 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 ============= Filename Records Start Stop ----------------------------------------------------------------------- Volume ID: VGPR_1201 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

6) VG1 SAT PRA CALIBRATED HI-RES LOW FREQ. REC. BAND DATA V1.0 maxmize
Resource ID:spase://VMO/NumericalData/Voyager1/PRA/Saturn/PT6S
Start:1980-11-11 22:09:23 Observatory:Voyager 1 Cadence:6 seconds
Stop:1980-11-16 23:59:47 Instrument:Voyager 1 Planetary Radio Astronomy (PRA) experiment Resource:NumericalData
Data Set Overview ================= This data set (VG1-S-PRA-3-RDR-LOWBAND-6SEC-V1.0) contains data acquired by the Voyager-1 Planetary Radio Astronomy (PRA) instrument during the Saturn encounter. Since the PRA instrument is able to observe planetary phenomenon at much larger ranges than other fields and particles experiments, thus the PRA data cover a variable and longer encounter period. PRA lowband data provided here cover the entire Saturn Encounter Phase (1981-06-05 to 1981-09-28). VG1-S-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 corresponds, 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 space 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 [LEBLANCETAL1987]. Missing or bad data values are set to zero. If the status word is zero, any data in that receiver sweep should be discarded.

7) 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.

8) 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.

9) 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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