diff --git a/apps/modes_rx b/apps/modes_rx
index c4f9eb0..6a1fcc1 100755
--- a/apps/modes_rx
+++ b/apps/modes_rx
@@ -19,8 +19,6 @@
 # Boston, MA 02110-1301, USA.
 # 
 
-my_position = None
-
 from gnuradio.eng_option import eng_option
 from optparse import OptionParser
 import time, os, sys, threading
@@ -28,11 +26,33 @@ from string import split, join
 import air_modes
 import csv
 from air_modes.exceptions import *
+import zmq
 
-def printraw(msg):
-    print msg
+class screen_printer(threading.Thread):
+    def __init__(self, position, context):
+        threading.Thread.__init__(self)
+        self._subscriber = context.socket(zmq.SUB)
+        self._subscriber.connect("inproc://modes-radio-pub")
+        self._subscriber.setsockopt(zmq.SUBSCRIBE, "dl_data")
 
-if __name__ == '__main__':
+        self._printer = air_modes.output_print(position)
+        self.done = False
+        self.setDaemon(True)
+        self.start()
+
+    def run(self):
+        while not self.done:
+            [address, msg] = self._subscriber.recv_multipart() #blocking
+            try:
+                self._printer.output(msg)
+            except ADSBError:
+                pass
+
+        self._subscriber.close()
+        
+
+def main():
+  my_position = None
   usage = "%prog: [options] output filename"
   parser = OptionParser(option_class=eng_option, usage=usage)
   parser.add_option("-R", "--subdev", type="string",
@@ -49,8 +69,6 @@ if __name__ == '__main__':
                       help="set ADC sample rate [default=%default]")
   parser.add_option("-T", "--threshold", type="eng_float", default=5.0,
                       help="set pulse detection threshold above noise in dB [default=%default]")
-  parser.add_option("-a","--output-all", action="store_true", default=False,
-                      help="output all frames")
   parser.add_option("-F","--filename", type="string", default=None,
                       help="read data from file instead of USRP")
   parser.add_option("-K","--kml", type="string", default=None,
@@ -67,65 +85,64 @@ if __name__ == '__main__':
                       help="Use UDP source on specified port")
   parser.add_option("-m","--multiplayer", type="string", default=None,
                       help="FlightGear server to send aircraft data, in format host:port")
-  parser.add_option("-d","--rtlsdr", action="store_true", default=False,
-                      help="Use RTLSDR dongle instead of UHD source")
+  parser.add_option("-o","--osmocom", action="store_true", default=False,
+                      help="Use gr-osmocom source (RTLSDR or HackRF) instead of UHD source")
   parser.add_option("-p","--pmf", action="store_true", default=False,
                       help="Use pulse matched filtering")
-                      
+
   (options, args) = parser.parse_args()
 
-  tb = air_modes.modes_radio(options)
-
-  updates = []
+  #construct the radio
+  context = zmq.Context(1)
+  tb = air_modes.modes_radio(options, context)
+  tb.start()
+  #tb will publish via ZMQ on the "radio-pub" feed
+  #clients connect to tb socket and do things.
+  #the radio-pub feed is channelized into "dl_data" and (not yet)
+  #"ul_data" which correspond to downlink and uplink data
 
   if options.location is not None:
     reader = csv.reader([options.location], quoting=csv.QUOTE_NONNUMERIC)
     my_position = reader.next()
 
-  if options.raw is True:
-    rawport = air_modes.raw_server(9988) #port
-    tb.subscribe('dl_data', rawport.output)
-    tb.subscribe('dl_data', printraw)
-    updates.append(rawport.add_pending_conns)
-
   if options.kml is not None:
     #we spawn a thread to run every 30 seconds (or whatever) to generate KML
     dbname = 'adsb.db'
-    lock = threading.Lock()
-    sqldb = air_modes.output_sql(my_position, dbname, lock) #input into the db
-    kmlgen = air_modes.output_kml(options.kml, dbname, my_position, lock) #create a KML generating thread to read from the db
-    tb.subscribe('dl_data', sqldb.output)
+    sqldb = air_modes.output_sql(my_position, dbname, context) #input into the db
+    #kmlgen = air_modes.output_kml(options.kml, dbname, my_position, lock) #create a KML generating thread to read from the db
+    #tb.subscribe('dl_data', sqldb.output)
 
-  if options.sbs1 is True:
-    sbs1port = air_modes.output_sbs1(my_position, 30003)
-    tb.subscribe('dl_data', sbs1port.output)
-    updates.append(sbs1port.add_pending_conns)
-    
+#  if options.sbs1 is True:
+#    sbs1port = air_modes.output_sbs1(my_position, 30003)
+#    tb.subscribe('dl_data', sbs1port.output)
+    #updates.append(sbs1port.add_pending_conns)
+
+  printer = None
   if options.no_print is not True:
-    tb.subscribe('dl_data', air_modes.output_print(my_position).output)
+    printer = screen_printer(my_position, context)
 
-  if options.multiplayer is not None:
-    [fghost, fgport] = options.multiplayer.split(':')
-    fgout = air_modes.output_flightgear(my_position, fghost, int(fgport))
-    tb.subscribe('dl_data', fgout.output)
-
-  tb.start()
-
-  while 1:
-    try:
-      #the update registry is really for the SBS1 and raw server plugins -- we're looking for new TCP connections.
-      #i think we have to do this here rather than in the output handler because otherwise connections will stack up
-      #until the next output arrives
-      for update in updates:
-        update()
-      time.sleep(0.1)
-      
-    except KeyboardInterrupt:
-      break
-
-  tb.stop()
-  tb.wait()
-  if options.kml is not None:
-    kmlgen.done = True
+#  if options.multiplayer is not None:
+#    [fghost, fgport] = options.multiplayer.split(':')
+#    fgout = air_modes.output_flightgear(my_position, fghost, int(fgport))
+#    tb.subscribe('dl_data', fgout.output)
 
+  #start an updater thread to handle adding/removing TCP connections
+  #TODO this can be removed when we start using 0MQ
+#  updater = threading.Thread(target=timed_callback, args=(updates,))
+#  updater.setDaemon(True)
+#  updater.start()
   
+  tb.wait()
+
+  if printer is not None:
+    printer.done = True
+    #printer.join()
+  if options.kml is not None:
+    sqldb.done = True
+    #sqldb.join()
+
+  time.sleep(0.1)
+
+
+if __name__ == '__main__':
+  main()
diff --git a/python/kml.py b/python/kml.py
index 908a4ab..973f070 100644
--- a/python/kml.py
+++ b/python/kml.py
@@ -39,7 +39,7 @@ class output_kml(threading.Thread):
         self._db = sqlite3.connect(self._dbname) #read from the db
         while self.done is False:
             self.writekml()
-            time.sleep(self._timeout) 
+            time.sleep(self._timeout)
                 
         self.done = True
         self._db.close()
diff --git a/python/radio.py b/python/radio.py
index 6449483..7aeea32 100644
--- a/python/radio.py
+++ b/python/radio.py
@@ -25,15 +25,39 @@
 
 from gnuradio import gr, gru, optfir, eng_notation, blks2
 from gnuradio.eng_option import eng_option
-from gnuradio.gr.pubsub import pubsub
 import air_modes
+import zmq
+import threading
+import time
 
-DOWNLINK_DATA_TYPE = 'dl_data'
+DOWNLINK_DATA_TYPE = "dl_data"
 
-class modes_radio (gr.top_block, pubsub):
-  def __init__(self, options):
+#ZMQ message publisher.
+#TODO: limit high water mark
+#TODO: limit number of subscribers
+class radio_publisher(threading.Thread):
+  def __init__(self, port, context, queue):
+    threading.Thread.__init__(self)
+    self._queue = queue
+    self._publisher = context.socket(zmq.PUB)
+    if port is None:
+      self._publisher.bind("inproc://modes-radio-pub")
+    else:
+      self._publisher.bind("tcp://*:%i" % port)
+
+    self.setDaemon(True)
+    self.done = False
+
+  def run(self):
+    while self.done is False:
+      while not self._queue.empty_p():
+        self._publisher.send_multipart([DOWNLINK_DATA_TYPE, self._queue.delete_head().to_string()])
+      time.sleep(0.1) #can use time.sleep(0) to yield, but it'll suck a whole CPU
+      
+
+class modes_radio (gr.top_block):
+  def __init__(self, options, context):
     gr.top_block.__init__(self)
-    pubsub.__init__(self)
     self._options = options
     self._queue = gr.msg_queue()
     
@@ -43,14 +67,6 @@ class modes_radio (gr.top_block, pubsub):
 
     self._setup_source(options)
 
-    self.subscribe('gain', self.set_gain)
-    self.subscribe('freq', self.set_freq)
-
-    self['gain'] = options.gain
-    self['freq'] = options.freq
-    self['rate'] = options.rate
-    self['filename'] = options.filename
-
     #TODO allow setting rate, threshold (drill down into slicer & preamble)
 
     self.rx_path = air_modes.rx_path(rate, options.threshold, self._queue, options.pmf)
@@ -63,10 +79,8 @@ class modes_radio (gr.top_block, pubsub):
         self.connect(self._u, self.rx_path)
 
     #Publish messages when they come back off the queue
-    self._async_rcv = gru.msgq_runner(self._queue, self.async_callback)
-
-  def async_callback(self, msg):
-    self[DOWNLINK_DATA_TYPE] = msg.to_string()
+    self._pubsub = radio_publisher(None, context, self._queue)
+    self._pubsub.start()
 
   #these are wrapped with try/except because file sources and udp sources
   #don't have set_center_freq/set_gain functions. this should check to see
@@ -85,7 +99,7 @@ class modes_radio (gr.top_block, pubsub):
         pass
 
   def _setup_source(self, options):
-    if options.filename is None and options.udp is None and options.rtlsdr is None:
+    if options.filename is None and options.udp is None and options.osmocom is None:
       #UHD source by default
       from gnuradio import uhd
       self._u = uhd.single_usrp_source(options.args, uhd.io_type_t.COMPLEX_FLOAT32, 1)
@@ -105,8 +119,8 @@ class modes_radio (gr.top_block, pubsub):
       if options.antenna is not None:
         self._u.set_antenna(options.antenna)
 
-      self._u.set_samp_rate(rate)
-      rate = int(self._u.get_samp_rate()) #retrieve actual
+      self._u.set_samp_rate(options.rate)
+      options.rate = int(self._u.get_samp_rate()) #retrieve actual
 
       if options.gain is None: #set to halfway
         g = self._u.get_gain_range()
@@ -115,18 +129,26 @@ class modes_radio (gr.top_block, pubsub):
       print "Setting gain to %i" % options.gain
       self._u.set_gain(options.gain)
       print "Gain is %i" % self._u.get_gain()
-      
-    elif options.rtlsdr: #RTLSDR dongle
+
+    #TODO: detect if you're using an RTLSDR or Jawbreaker
+    #and set up accordingly.
+    #ALSO TODO: Actually set gain appropriately using gain bins in HackRF driver.
+    elif options.osmocom: #RTLSDR dongle or HackRF Jawbreaker
         import osmosdr
         self._u = osmosdr.source_c(options.args)
-        self._u.set_sample_rate(3.2e6) #fixed for RTL dongles
+#        self._u.set_sample_rate(3.2e6) #fixed for RTL dongles
+        self._u.set_sample_rate(options.rate)
         if not self._u.set_center_freq(options.freq):
             print "Failed to set initial frequency"
 
         self._u.set_gain_mode(0) #manual gain mode
         if options.gain is None:
             options.gain = 34
-            
+###DO NOT COMMIT
+        self._u.set_gain(14, "RF", 0)
+        self._u.set_gain(40, "IF", 0)
+        self._u.set_gain(14, "RF", 0)
+###DO NOT COMMIT
         self._u.set_gain(options.gain)
         print "Gain is %i" % self._u.get_gain()
 
diff --git a/python/sql.py b/python/sql.py
index 585e35d..d41f01f 100644
--- a/python/sql.py
+++ b/python/sql.py
@@ -24,18 +24,25 @@ from string import split, join
 import air_modes
 import sqlite3
 from air_modes.exceptions import *
+import zmq
 
-class output_sql(air_modes.parse):
-  def __init__(self, mypos, filename, lock):
+class output_sql(air_modes.parse, threading.Thread):
+  def __init__(self, mypos, filename, context):
+    threading.Thread.__init__(self)
     air_modes.parse.__init__(self, mypos)
 
-    self._lock = lock
+    #init socket
+    self._subscriber = context.socket(zmq.SUB)
+    self._subscriber.connect("inproc://modes-radio-pub") #TODO allow spec addr
+    self._subscriber.setsockopt(zmq.SUBSCRIBE, "dl_data")
+
+    self._lock = threading.Lock()
     with self._lock:
       #create the database
       self.filename = filename
-      self.db = sqlite3.connect(filename)
+      self._db = sqlite3.connect(filename)
       #now execute a schema to create the tables you need
-      c = self.db.cursor()
+      c = self._db.cursor()
       query = """CREATE TABLE IF NOT EXISTS "positions" (
                 "icao" INTEGER KEY NOT NULL,
                 "seen" TEXT NOT NULL,
@@ -58,30 +65,42 @@ class output_sql(air_modes.parse):
             );"""
       c.execute(query)
       c.close()
-      self.db.commit()
+      self._db.commit()
       #we close the db conn now to reopen it in the output() thread context.
-      self.db.close()
-      self.db = None
+      self._db.close()
+      self._db = None
 
-  def __del__(self):
-    self.db = None
+      self.setDaemon(True)
+      self.done = False
+      self.start()
 
-  def output(self, message):
+  def run(self):
+    while not self.done:
+        [address, msg] = self._subscriber.recv_multipart() #blocking
+        try:
+            self.insert(msg)
+        except ADSBError:
+            pass
+
+    self._subscriber.close()
+    self._db = None
+
+  def insert(self, message):
     with self._lock:
       try:
         #we're checking to see if the db is empty, and creating the db object
         #if it is. the reason for this is so that the db writing is done within
         #the thread context of output(), rather than the thread context of the
-        #constructor. that way you can spawn a thread to do output().
-        if self.db is None:
-          self.db = sqlite3.connect(self.filename)
+        #constructor.
+        if self._db is None:
+          self._db = sqlite3.connect(self.filename)
           
         query = self.make_insert_query(message)
         if query is not None:
-            c = self.db.cursor()
+            c = self._db.cursor()
             c.execute(query)
             c.close()
-            self.db.commit()
+            self._db.commit()
 
       except ADSBError:
         pass