enable acars as a background decoding service

owrx/modes.py

@@ -206,6 +206,7 @@ class Modes(object):
             underlying=["empty"],
             bandpass=Bandpass(-2500, 2500),
             requirements=["acarsdec"],
+            service=True,
             squelch=False,
         )
     ]

owrx/service/__init__.py

@@ -321,6 +321,9 @@ class ServiceHandler(SdrSourceEventClient):
         elif mod == "vdl2":
             from csdr.chain.dumpvdl2 import DumpVDL2
             return DumpVDL2()
+        elif mod == "acars":
+            from csdr.chain.acarsdec import AcarsDec
+            return AcarsDec()
 
         raise ValueError("unsupported service modulation: {}".format(mod))