diff --git a/lib/xmet/raob.py b/lib/xmet/raob.py
index 1f83d87..72386c7 100644
--- a/lib/xmet/raob.py
+++ b/lib/xmet/raob.py
@@ -13,13 +13,9 @@ CHUNK_STRIP_CHARS = "\x01\x03\x0a\x20"
 class RAOBReaderException(Exception):
     ...
 
-class RAOBSounding():
-    def __init__(self):
-        self.timestamp: datetime.datetime    = None
-        self.station:   int                  = None
-        self.samples:   list[SoundingSample] = list()
-
 class RAOBObs():
+    DATA_SOURCE = 'UCAR'
+
     def __init__(self, kind: str):
         self.kind:   str       = kind
         self.tokens: list[str] = list()
@@ -214,7 +210,7 @@ class RAOBObs():
 
         return sample
 
-    def parse_ttaa(self) -> RAOBSounding:
+    def parse_ttaa(self) -> Sounding:
         #
         # Return None if there is no height data up to 100mb.
         #
@@ -232,10 +228,16 @@ class RAOBObs():
         if sample is None:
             return
 
-        sounding = RAOBSounding()
-        sounding.timestamp = self.parse_timestamp(self.tokens[0])
-        sounding.station   = int(self.tokens[1])
-        sounding.samples.append(sample)
+        timestamp = self.parse_timestamp(self.tokens[0])
+
+        sounding = Sounding()
+        sounding.samples = [sample]
+        sounding.station = self.tokens[1]
+
+        sounding.data_source_pressure = self.DATA_SOURCE
+        sounding.data_source_other    = self.DATA_SOURCE
+        sounding.timestamp_observed   = timestamp
+        sounding.timestamp_released   = timestamp - datetime.timedelta(minutes=45)
 
         for i in range(5, len(self.tokens), 3):
             if len(self.tokens) < i+3 or self.tokens[i][-1] == '=':