SGP/SONDE/B4 - B4 sounding contaminated by interference

Much of this sounding is contaminated, apparently by interference from another sonde 
signal.  It is still no clear why this seems to happen more frequently at B4 than the other 
sites, especially since the wind seems to have been from the west and B4 should be the most 
upwind station.

• Dewpoint Temperature(dp)
• Ascent rate(asc)
• North Latitude(lat)
• Wind Speed(wspd)
• base time in epoch(base_time)
• -180.0 - +180.0(alt)
• Dry Bulb Temperature(tdry)
• Easterly Wind Component(u_wind)
• Wind status(wstat)
• V wind component(v_wind)
• Retrieved pressure profile(pres)
• Wind Direction(deg)
• Time offset from base_time(time_offset)
• lon(lon)
• Relative Humidity (hybrid-b grid)(rh)

• (Raw data stream - documentation not supported)

• Dry Bulb Temperature(tdry)
• Retrieved pressure profile(pres)
• Relative Humidity (hybrid-b grid)(rh)
• lon(lon)
• Wind Direction(deg)
• Wind status(wstat)
• Easterly Wind Component(u_wind)
• Ascent rate(asc)
• base time in epoch(base_time)
• -180.0 - +180.0(alt)
• Dewpoint Temperature(dp)
• V wind component(v_wind)
• North Latitude(lat)
• Wind Speed(wspd)
• Time offset from base_time(time_offset)