ADS-B Receiver is a fun project. With some pretty cheap hardware, you can track nearby planes.

Warning: This turned out way longer than I expected.

I'm in the US and I don't know how this would work with sensors that are available in Europe, but I'll share what I've been having success with lately.

I've been using cheap 433MHz sensors to measure temperature in a couple of locations using an RTL2832-based receiver (The one I'm using is a NooElec NESDR Mini 2+) and rtl_433.

I start rtl_433 in a screen session with the command:

rtl_433 -F json | mosquitto_pub -t home/rtl_433 -l

This tells rtl_433 to output in json format and pipes the result to mosquitto_pub (telling it to read from stdin with '-l').

On the MQTT side, the messages from my sensors appear formatted like this:

home/rtl_433 {"time" : "2017-04-10 15:06:11", "brand" : "OS", "model" : "THGR122N", "id" : 7, "channel" : 2, "battery" : "OK", "temperature_C" : 12.700, "humidity" : 23}
home/rtl_433 {"time" : "2017-04-10 15:06:15", "temperature" : 45.140, "humidity" : 70, "id" : 103, "model" : "LaCrosse TX141TH-Bv2 sensor", "battery" : "OK", "test" : "No"}
home/rtl_433 {"time" : "2017-04-10 15:06:51", "brand" : "OS", "model" : "THGR122N", "id" : 7, "channel" : 2, "battery" : "OK", "temperature_C" : 12.700, "humidity" : 23}
home/rtl_433 {"time" : "2017-04-10 15:06:52", "brand" : "OS", "model" : "THGR122N", "id" : 7, "channel" : 2, "battery" : "OK", "temperature_C" : 12.700, "humidity" : 23}

This is all nothing special. All of this stuff I just happened to have. The RTL2832 from a radio project I had been toying with. The sensors are a re-branded Oregon Scientific from an old, defunct temp/hygrometer, as well as the sensor from a LaCrosse weather station that I picked up on clearance a while back.

To get it into HA my config looks like this:

################

MQTT sensors #

################<br />

## rtl_433<br />
##<br />

# LaCrosse TX141TH-Bv2 sensor<br />
#<br />

Temperature

- platform: mqtt<br />
  name: &quot;rtl_433_lacrossetx141thbv2_temperature&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 103 and value_json.model == 'LaCrosse TX141TH-Bv2 sensor' %} {{ value_json.temperature }} {% else %} {{ states.sensor.rtl_433_lacrossetx141thbv2_temperature.state | is_defined }} {% endif %}&quot;<br />

Humidity

- platform: mqtt<br />
  name: &quot;rtl_433_lacrossetx141thbv2_humidity&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 103 and value_json.model == 'LaCrosse TX141TH-Bv2 sensor' %} {{ value_json.humidity }} {% else %} {{ states.sensor.rtl_433_lacrossetx141thbv2_humidity.state | is_defined }} {% endif %}&quot;<br />

Battery

- platform: mqtt<br />
  name: &quot;rtl_433_lacrossetx141thbv2_battery&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 103 and value_json.model == 'LaCrosse TX141TH-Bv2 sensor' %} {{ value_json.battery }} {% else %} {{ states.sensor.rtl_433_lacrossetx141thbv2_battery.state | is_defined }} {% endif %}&quot;<br />

# Oregon Scientific THGR122N<br />
#<br />

Temperature

- platform: mqtt<br />
  name: &quot;rtl_433_oregonthgr122n_temperature&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 7 and value_json.model == 'THGR122N' %} {{ value_json.temperature_C }} {% else %} {{ states.sensor.rtl_433_oregonthgr122n_temperature.state | is_defined }} {% endif %}&quot;<br />

Humidity

- platform: mqtt<br />
  name: &quot;rtl_433_oregonthgr122n_humidity&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 7 and value_json.model == 'THGR122N' %} {{ value_json.humidity }} {% else %} {{ states.sensor.rtl_433_oregonthgr122n_humidity.state | is_defined }} {% endif %}&quot;<br />

Battery

- platform: mqtt<br />
  name: &quot;rtl_433_oregonthgr122n_battery&quot;<br />
  state_topic: &quot;home/rtl_433&quot;<br />
  value_template: &quot;{% if value_json.id == 7 and value_json.model == 'THGR122N' %} {{ value_json.battery }} {% else %} {{ states.sensor.rtl_433_oregonthgr122n_battery.state | is_defined }} {% endif %}&quot;<br />

Then I use a template to format it for display:

## Template Sensors<br />
##<br />

# LaCrosse TX141TH-Bv2 sensor (sensors_mqtt.yaml)<br />
#<br />

Outdoor Temperature

- platform: template<br />
  sensors:<br />
    sensor_temperature_outdoor:<br />
      value_template: '{{ states.sensor.rtl_433_lacrossetx141thbv2_temperature.state|round(1) }}'<br />
      icon_template: 'mdi:thermometer'<br />
      entity_id: sensor.rtl_433_lacrossetx141thbv2_temperature<br />
      friendly_name: &quot;Outdoor Temperature&quot;<br />
      unit_of_measurement: '°F'<br />

Outdoor Humidity

- platform: template<br />
  sensors:<br />
    sensor_humidity_outdoor:<br />
      value_template: '{{ states.sensor.rtl_433_lacrossetx141thbv2_humidity.state }}'<br />
      icon_template: 'mdi:gauge'<br />
      entity_id: sensor.rtl_433_lacrossetx141thbv2_humidity<br />
      friendly_name: &quot;Outdoor Humidity&quot;<br />
      unit_of_measurement: '%'<br />
<br />
# Battery<br />
- platform: template<br />
  sensors:<br />
    sensor_battery_lacrossetx141th:<br />
      value_template: '{{ states.sensor.rtl_433_lacrossetx141thbv2_battery.state }}'<br />
      icon_template: '{% if states.sensor.rtl_433_lacrossetx141thbv2_battery.state == &quot;OK&quot; %} mdi:battery {% else %} mdi:battery-outline {% endif %}'<br />
      entity_id: sensor.rtl_433_lacrossetx141thbv2_battery<br />
      friendly_name: &quot;LaCrosse TX141TH-Bv2 Battery&quot;<br />

# Oregon Scientific THGR122N (sensors_mqtt.yaml)<br />
#<br />

Garage Temperature

- platform: template<br />
  sensors:<br />
    sensor_temperature_garage:<br />
      value_template: '{{ ((float(states.sensor.rtl_433_oregonthgr122n_temperature.state)* 9 / 5)+ 32)|round(1) }}'<br />
      icon_template: 'mdi:thermometer'<br />
      entity_id: sensor.rtl_433_oregonthgr122n_temperature<br />
      friendly_name: &quot;Garage Temperature&quot;<br />
      unit_of_measurement: '°F'<br />

Garage Humidity

- platform: template<br />
  sensors:<br />
    sensor_humidity_garage:<br />
      value_template: '{{ states.sensor.rtl_433_oregonthgr122n_humidity.state|round(0)|int }}'<br />
      icon_template: 'mdi:gauge'<br />
      entity_id: sensor.rtl_433_oregonthgr122n_humidity<br />
      friendly_name: &quot;Garage Humidity&quot;<br />
      unit_of_measurement: '%'<br />
<br />
# Battery<br />
- platform: template<br />
  sensors:<br />
    sensor_battery_oregonthgr122n:<br />
      value_template: '{{ states.sensor.rtl_433_oregonthgr122n_battery.state }}'<br />
      icon_template: '{% if states.sensor.rtl_433_oregonthgr122n_battery.state == &quot;OK&quot; %} mdi:battery {% else %} mdi:battery-outline {% endif %}'<br />
      entity_id: sensor.rtl_433_oregonthgr122n_battery<br />
      friendly_name: &quot;Oregon THGR122N Battery&quot;<br />

The end result, I get some cards and graphs. Woohoo!

As it see it, the pros of this approach are:

• Cheap (Most people already have some of the sensors for their remote thermometer).
  
• Hardware is easy to implement as you don't have to build it yourself.
  
  The cons:
  
  
• Complicated setup. Requires linux. Requires setup of rtl_433 and mqtt. If you're particular about your usb devices staying put in /dev, requires some config in udev. May require blacklisting in modprobe.d (specifically dvb_usb_rtl28xxu, rtl2832, and rtl2830 to free up the device for rtl_433 to use.) If you aren't intimately familiar with your particular linux distro, by the time you get done setting this up you will be.
  
• These sensors change their ID every time you change the battery. If you're using the device ID in your config to differentiate between sensors (I am) you need to remember this.
  
• If you have neighbors with sensors you might have to do a bit of experimenting to figure out which sensors are yours and which ones are theirs.
  

You need a compatible LNB on the dish and an RTL-SDR dongle, like https://www.amazon.com/NooElec-NESDR-Mini-Receiver-RTL2832U/dp/B00VZ1AWQA

There are open source SDRs out there too... though they're fancier ones than the RTL-SDRs. In any case, it's all off the shelf parts. One of our major goals in this was to make the reception really low cost: the system is most useful if there are many receivers.

(Before you go rushing out to buy one: We don't cover Thailand yet. We need to build another uplink location out to cover that slice of the world. We're working on it!)

Either of these are going to do the job just fine. Expect to spend about a hundred bucks.

http://www.amazon.com/Uniden-Bearcat-Channel-Numeric-BC125AT/dp/B00772MR0K

http://www.amazon.com/Uniden-Channel-Scanner-Weather-BC345CRS/dp/B00ALNPM2C

(edit: Removed the scanners that couldn't receive mil-air frequencies)

Take your pick between handheld or base scanner.

The Uniden BCT15X is a nice mid range base scanner for a little bit more.

http://www.amazon.com/Uniden-BearTracker-Tracking-Scanner-Support/dp/B002IT1C8U

Another good and cheap option is RTL-SDR. These inexpensive dongles are used with your computer and open up a whole world of cool stuff to do, from just basic listening to more advanced projects.

http://www.amazon.com/NooElec-NESDR-Mini-Compatible-Guaranteed/dp/B00VZ1AWQA

Here is the radio I am using and here is the tutorial on finding police frequencys and decoding them. I bought it to better understand radio waves for my signal analysis class and use it for days like these.

Thanks! I will start with something cheaper, but I understand is good quality.

I bought this https://www.amazon.it/gp/product/B00VZ1AWQA/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

It seems good enough for me even if it doesn't catch HF. Besides I would have problems with a long antenna anyway.

My next move will be an upconverter, maybe I can use a fraction of antenna, IDK. I still don't get what are good ratios of Antenna length/Lambda, but we will see. Thank you!

Thanks Everyone, I went ahead and just bought 2 new RTLSDR (https://www.amazon.com/gp/product/B00VZ1AWQA/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1) and some adapters for now (https://www.amazon.com/gp/product/B00RF15070/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1) Im hoping to use unitrunker with the 2 dongles and then eventually make an antenna to get NOAA Images

I just have the generic $20 NooElec. The cheaper ones may work too but I don't have any experience

these are the blog SDRs
http://www.amazon.com/NooElec-NESDR-Mini-RTL2832-Antenna/dp/B00P2UOU72/ref=sr_1_1?ie=UTF8&qid=1450573736&sr=8-1&keywords=nooelec

and this is the new one..

http://www.amazon.com/NooElec-NESDR-Mini-Compatible-Guaranteed/dp/B00VZ1AWQA/ref=sr_1_2?ie=UTF8&qid=1450573736&sr=8-2&keywords=nooelec

which one are you ACTUALLY using..

To get started you'll need:

• An RTL-SDR (I've used these two with success: 1 2)
  
• Zadig & Install-RTL-SDR
  
• dump978 source
  
• compiler (I used Visual Studio)
  
  Once you have the pieces, you'll need to:
  
  
• Install RTL-SDR following their instructions
  
• Build dump978 and uat2Text
  
• Run rtl_sdr -f 978000000 -s 2083334 - | dump978.exe | uat2text.exe and see some output.
  
• uat2Text is useful to make sure you are receiving UAT data, but not the greatest as an intermediate step in processing data
  
• Figure out some way to convert the demodulated UAT frames into something your application can use (maybe gen_gdl90).
  
• The best option here really depends on what you want as input on your display: GDL-90, just a list of lat/lons, a json request interface, etc.

Would this be any good?