This data set consists of
electric field waveform samples from the Voyager 2 Plasma Wave
Receiver waveform receiver obtained during the Uranus encounter.
The waveforms are collections of 4-bit samples of the electric
field measured by the dipole electric antenna at a rate of 28,800
samples per second.  1600 samples are collected in 55.56 msec
followed by a 4.44-msec gap. Each 60-msec interval constitutes a
line of waveform samples. The data set includes about 271 frames of
waveform samples consisting of up to 800 lines, each.  The
telemetry format for the waveform data is identical to that for
images, hence the use of line and frame as constructs in describing
the form of the data.  The waveform is sampled through a bandpass
filter with a passband of 40 Hz to 12 kHz.  The 4-bit samples
provide sixteen digital values of the electric field with a
linear amplitude scale, but the amplitude scale is arbitrary
because of the automatic gain control used in the waveform
receiver.  The instantaneous dynamic range afforded by the 4
bit samples is about 23 db, but the automatic gain control allows
the dominant signal in the passband to be set at the optimum
level to fit within the instantaneous dynamic range.  With the gain
control, the overall dynamic range of the waveform receiver
is about 100 db.  The automatic gain control gain setting is not
returned to the ground, hence, there is no absolute calibration
for the data.  However, by comparing the waveform spectrum derived
by Fourier transforming the waveform to the spectrum provided by
the spectrum analyzer data, an absolute calibration may be
obtained in most cases.  The data may be plotted in raw form to
show the actual waveform; this is useful for studying events such
as dust impacts on the spacecraft.  But the normal method of
analyzing the waveform data is by Fourier transforming the samples
from each line to arrive at an amplitude versus frequency spectrum.
By stacking the spectra side-by-side in time order, a frequency-
time spectrogram can be produced.
Additional information about this dataset and the instrument which
produced it can be found elsewhere in this catalog.  An overview of
the data in this data set can be found in Gurnett et al. [1986] and
a complete instrument description can be found in Scarf and Gurnett
[1977].

     SAMPLING_PARAMETER_NAME        = TIME
     SAMPLING_PARAMETER_RESOLUTION  = 0.000034722
     MINIMUM_SAMPLING_PARAMETER     = N/A
     MAXIMUM_SAMPLING_PARAMETER     = N/A
     SAMPLING_PARAMETER_INTERVAL    = 0.000034722
     MINIMUM_AVAILABLE_SAMPLING_INT = 0.000034722
     SAMPLING_PARAMETER_UNIT        = SECOND
     DATA_SET_PARAMETER_NAME        = PLASMA WAVE WAVEFORM
     NOISE_LEVEL                    = 0.000005
     DATA_SET_PARAMETER_UNIT        = VOLT/METER
       (Data not absolutely calibrated)

This data set includes all available waveform receiver data
obtained during the Uranus encounter.  There has been no attempt
to clean various interference signals from the data.  Most of these
can normally be easily seen in frequency-time spectrograms as
narrowband, fixed-frequency tones.  The most common include narrow-
band tones at 2.4 and 4.8 kHz which are power supply harmonics.
There is sometimes a tone near 1.7 kHz which is associated with
the operation of the spacecraft gyros.  The spacecraft tape
recorder results in a rather intense band in the frequency range
of a few hundred Hz.  There are few times when the data in this
frequency range can be used.  However, there are times when the
real signals in this frequency range can exceed the intensity of
the interference sufficiently so that the frequency range near
a few hundred Hz can be used.  Use of the spectrum analyzer data
can be of use to determine when these time periods occur.  The
stepper motor of the LECP instrument also interferes in the
frequency range of a few hundred Hz, but for periods of a few
seconds.
The LECP interference is very intense and captures the automatic
gain control so that real signals, even where there is no
interference, will appear to decrease in amplitude until the LECP
interference fades in amplitude.  The PLS instrument periodically
interferes at 400 Hz and odd harmonics because of a 400-Hz square
wave used to modulate a grid in the detector.  The PLS interference
lasts for several seconds and ends abruptly.  Telemetry errors
result in a fairly graceful degradation of the waveform data.
Assuming the telemetry errors are randomly occurring bursts, they
typically appear as an enhanced background level in the spectrum.
Since the bursts are short, their Fourier transform is a broadband
spectrum. When looking for relatively narrowband features or
features with distinct frequency-time characteristics, the result
of the bursts simply reduce the signal-to-noise in the spectrum.
One way of reducing the effect of burst telemetry errors is to pass
the waveform data through a low-pass filter to despike it, prior to
running the Fourier transform.  The waveform data is not subject
to the negative effects of the failure in the Voyager 2 Flight
Data System which reduces the sensitivity of the spectrum analyzer
and affects the calibration above 1 kHz.  In fact, use of the 1 -
12 kHz waveform data is an effective way of avoiding the problems
with the spectrum analyzer data in this frequency range.