diff --git a/models/Observer.model b/models/Observer.model
new file mode 100644
index 0000000..20a9fd7
--- /dev/null
+++ b/models/Observer.model
@@ -0,0 +1,35 @@
+init{
+    weather := 0
+    orcs := nil
+    hobbits := nil
+    logger := "not_started"
+}
+
+channel CIO1{
+    out weather(time:Int, timePasses(nil)) == mod(time + 1,2)
+}
+
+channel CIO2{
+    out orcs(o:Tuple, update(id:Int, type:Str))==tuple(id,type)
+    out hobbits(h:Tuple, update(id:Int, type:Str))==tuple(id,type)
+}
+
+channel C1{
+    in weather(w:Int, update(w)) == w%2
+    out orcs(o2:Tuple, update(w)) == if(eq(w,fst(o2)), o2, nil)
+}
+
+channel C2{
+    in weather(w:Int, update(w)) == w%2
+    out hobbits(h2:Tuple, update(w)) == if(eq(w, fst(h2)), h2, nil)
+}
+
+channel C3{
+    in orcs(o:Tuple, setLog(o)) == o
+    out logger(l:Str, setLog(o)) == snd(o)
+}
+
+channel C4{
+    in hobbits(h:Tuple, setLog(h))== h
+    out logger(l, setLog(h)) == snd(h)
+}