Tagged: weather balloon

A Physical LED Vehicle HUD for KerberosSDR Radio Fox Hunting

Mark Jessop (@vk5qi) has recently been experimenting with a LED based hardware vehicle heads up display (HUD) that he has created to be used together with our KerberosSDR. The KerberosSDR combined with four antennas in a circular array determines the bearing towards a transmitter, and then the HUD displays this bearing visually on a circle.  

The HUD is cleverly designed so that the LEDs reflect on the windshield of the car, allowing for the lights to be safely seen on the windshield while driving. More videos of the HUD being developed and used can be seen on his Twitter feed.

In the video below Mark also shows how he combines KerberosSDR bearing data with his Chase Mapper software, which he uses for tracking down radiosonde weather balloons.

Mark's custom KerberosSDR HUD seen on Twitter

Mark writes:

For the last few months I've been piecing together a radio direction finding (also known as 'fox-hunting') system using a RTLSDR-Blog Kerberos-SDR, a custom-made antenna array, and my 'ChaseMapper' software. I have also recently added a 'heads up display' (HUD) box which displays the direction-of-arrival and SNR data from the Kerberos-SDR software.

I hope to put together a longer video showing how the system goes together sometime in the future, but this short clip shows how the system is used in the final approach to a radio transmitter (in this case, a 144 MHz transmitter from one of the Amateur Radio Experimenters Group organised night fox-hunts).

The antenna array consists of two 4-element nested arrays, one with 200mm antenna spacing for the 70cm band, and another with 425mm antenna spacing for the 2m band. The array is mounted to my car roof-racks, with phase-matched coax entering the car through a window-mounted bulkhead.

The red lines on the map indicate a bearing line produced by the Kerberos-SDR software. As we drive around the fox location, bearings are plotted, and we look for where they cross. There are always some inaccurate bearings due to multi-path issues, and misalignment between bearing acquisition time and the position/heading of the car, but it works well enough to be able to allow navigation to the transmitter location. The display can get fairly busy, so there are options to threshold by signal quality, and to 'age out' bearings over time.

The beeping noise you hear in the video is the signal from the radio transmitter, in this case a 144.390 MHz beacon which transmits short CW 'pips'. We were listening to the signal with an Icom IC-705 attached to an omnidirectional antenna so we knew when the transmitter started and stopped (and hence when to trust any bearings produced by the DoA system).

Towards the end of the video you can see the HUD in action, with the blue lights showing the estimated signal arrival direction, relative to the front of the car. As I slowly drive past the transmitter location (which I could see out the side of the car), the bearings swing to the right, and the SNR shows as being very strong. This is exactly what the display was intended for - it's not about getting hyper-accurate bearings, but more knowing when you need to turn left/right, or get out of the car!

Thanks to Will Anthony for capturing the video while I was driving!

Software used:

AREG Fox-hunt Activities: https://www.areg.org.au/archives/category/activities/fox-hunting

Finding a Radio Fox using a Kerberos-SDR + ChaseMapper

KerberosSDR is our 4-channel phase coherent capable RTL-SDR unit that we previously crowdfunded back in 2018. With a 4-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as four separate RTL-SDRs for multichannel monitoring.

KerberosSDR is soon to be replaced with the upgraded KrakenSDR, which will begin crowd funding on Crowd Supply later this year. Be sure to sign up on the Crowd Supply page to be updated once the campaign releases as due to long supply chain crisis related lead times, only a limited amount of stock will be initially available.

Andreas Spiess Tracks Weather Balloons with a TTGO LoRa Board and RTL-SDR

Earlier in August we posted about radiosondy.info and the MySondy radiosonde receiver. Radiosondy.info is an internet service that aggregates radiosonde weather balloon data received and decoded by RTL-SDR users all over the world. MySondy is a cheap TTGO LoRa receiver that is modified with custom firmware and combined with a companion Android app in order to create a portable radiosonde receiver. A radiosonde is a small sensor and radio package normally attached to a weather balloon. Meteorological agencies around the world typically launch two balloons a day from several locations to gather data for weather prediction. With cheap hardware like an RTL-SDR and the right decoding software it is possible to receive weather and GPS data from the weather balloons launched in your area. 

Over on his popular YouTube channel, Andreas Spiess "the guy with the Swiss accent" has uploaded a video featuring the RadioSondy and the MySondy receiver projects. In the video Andreas first explains what a radiosonde is, and who launches them. He goes on to show the RadioSondy website and how to track balloons on it. He then shows the portable MySondy receiver for tracking radiosondes, before finally showing how to set up a permanent fixed ground station with RTL-SDR and Raspberry Pi for contributing to the RadioSondy aggregation website.

In amongst the demonstrations he also goes on several hunts for weather balloons that have landed near him, ultimately recovering two radiosondes and one intact balloon. The radiosondes were initially tracked with the RadioSondy fixed RTL-SDR ground stations, then when in the vicinity of the landed balloon pinpointed and found with the MySondy hardware.

#360 Tracking and Chasing Weather Balloons with TTGO LoRa board and Raspberry Pi. Fun and adventure

TechMinds: How to Track Weather Balloons Using SDR

In his latest video Tech Minds has uploaded a video showing how to use an SDR to receive transmissions from radiosondes carried by weather balloons. Every day meteorological agencies around the world launch weather balloons several times a day. Each balloon carries a device called a radiosonde which continuously transmits weather telemetry to a ground station. With an SDR, antenna and free software it's possible to decode these radiosonde signals yourself from home.

In the video Tech Minds uses an RSPdx, SDRuno, VBCable and the RS41 Tracker software to receive telemetry from an RS-41 radiosonde launched in his area. We note that an RTL-SDR and SDR# could also be used. He shows the various bits of weather information available from the telemetry including information like temperature, pressure, humidity and the dew point. GPS and hardware status data is also available. Finally he shows how to view the balloon's flight path in Google Earth.

How To Track Weather Balloons Using SDR

Tracking and Recovering A NWS Weather Balloon & Radiosonde with an RTL-SDR

Over on YouTube OLHZN High Altitude Balloons has posted a very entertaining video showing how to use an RTL-SDR and small grid dish antenna to track and recover a fallen weather balloon and its radiosonde. OLHZN writes:

The US National Weather Service (#NWS) launches over 200 weather balloons everyday carrying an LMS-6 #radiosonde / rawinsonde made by Lockheed Martin to an altitude of over 100,000 ft. and you can track & follow the flights from home and even find the landing site and pick them up! This is a fun #DIY project that you can do yourself from home and I'll show you how to do it here along with some tips so you can go find yourself a weather balloon & radiosonde!

How to track & recover a NWS weather balloon & radiosonde 🎈🎈 Ham Radio DIY

Aggregating Weather Balloon Data Online with a Custom Raspberry Pi Image

Thanks to a RTL-SDR.COM reader for submitting a tip about radiosondy.info, a weather balloon data aggregation website made by SQ6KXY. Weather balloons carry a sensor and transmitter payload called a radiosonde. These radiosondes transmit their data to a ground station via an RF signal, which is typically at around 400 - 406 MHz in most countries. With an RTL-SDR and decoder software (related tutorial) it is possible to receive and decode their weather data, and also often their GPS location data. The location data can be used to find and collect radiosondes once they reach the ground.

SQ6KXY has created a website called radiosondy.info which aims to aggregate and make weather balloon data received by contributors public. It is similar to sites like flightradar24 which aggregate ADS-B data from aircraft. The main page allows you to view radiosondes that are currently flying, and the archive of previous flights.

To make contributing to the site as simple as possible, SQ6KXY has created a custom image for the Raspberry Pi, which is automatically generated by the website for your particular user account, local radiosonde frequency requirements, and number of SDRs. They don't specifically mention it, but we assume that contributors are mostly using RTL-SDRs in their receivers. The custom image is available for generation after signing up.

Web tool to generate a custom Raspberry Pi Image for Radiosonde Tracking
Web tool to generate a custom Raspberry Pi Image for Radiosonde Tracking

Reprogramming Vaisala RS-41 Radiosondes to Transmit APRS, RTTY, CW in the Ham or ISM Bands

Radiosondes are light weight sensor packages that are attached to weather balloons. They transmit live RF weather telemetry down to earth as they rise. With an RTL-SDR and appropriate antenna it can be possible to decode this telemetry. One related hobby that a few people enjoy is radiosonde chasing, which is tracking and collecting radiosondes once they have fallen back to the earth. Some people collect them as trophies, and others like to repurpose them. For example in this previous post we've seen how some radiosondes can be repurposed into L-band antennas for RTL-SDR's.

Another way to repurpose radiosondes has recently been submitted to us by regular contributor 'happysat' who wrote in and let us know that it is actually possible to reprogram the commonly used Vaisala RS-41 radiosondes into being able to transmit ham radio APRS, RTTY or CW mode signals in the ISM or ham bands. The initial hack was first performed by SQ5RWU, and then OM3BC who managed to create easier to use software that could reflash the radiosondes internal firmware via the serial port on the radiosonde. This hack could be useful for any ham requiring a cheap transmitter for their own high altitude balloon experiments.

Happysat ended up testing this software with some RS-41 radiosondes that he had, and managed to receive some generated signals with an RTL-SDR of his. Some photos that he's submitted are shown at the end of this post.

In addition to the above, happysat also wanted to mention his other radiosonde re-purposing project which was turning a DFM-06 and DFM-09 into a functional GPS unit that could be used for navigation when connected to a laptop, or to sync time on PCs.

Transmit APRS
PE2BZ's Modded RS41 with Solar Panels
RS41 Programmer
Transmit APRS PE2BZ's Modded RS41 with Solar Panels RS41 Programmer

A Physical LED Vehicle HUD for KerberosSDR Radio Fox Hunting

Mark Jessop (@vk5qi) has recently been experimenting with a LED based hardware vehicle heads up display (HUD) that he has created to be used together with our KerberosSDR. The KerberosSDR combined with four antennas in a circular array determines the bearing towards a transmitter, and then the HUD displays this bearing visually on a circle.  

The HUD is cleverly designed so that the LEDs reflect on the windshield of the car, allowing for the lights to be safely seen on the windshield while driving. More videos of the HUD being developed and used can be seen on his Twitter feed.

In the video below Mark also shows how he combines KerberosSDR bearing data with his Chase Mapper software, which he uses for tracking down radiosonde weather balloons.

Mark's custom KerberosSDR HUD seen on Twitter

Mark writes:

For the last few months I've been piecing together a radio direction finding (also known as 'fox-hunting') system using a RTLSDR-Blog Kerberos-SDR, a custom-made antenna array, and my 'ChaseMapper' software. I have also recently added a 'heads up display' (HUD) box which displays the direction-of-arrival and SNR data from the Kerberos-SDR software.

I hope to put together a longer video showing how the system goes together sometime in the future, but this short clip shows how the system is used in the final approach to a radio transmitter (in this case, a 144 MHz transmitter from one of the Amateur Radio Experimenters Group organised night fox-hunts).

The antenna array consists of two 4-element nested arrays, one with 200mm antenna spacing for the 70cm band, and another with 425mm antenna spacing for the 2m band. The array is mounted to my car roof-racks, with phase-matched coax entering the car through a window-mounted bulkhead.

The red lines on the map indicate a bearing line produced by the Kerberos-SDR software. As we drive around the fox location, bearings are plotted, and we look for where they cross. There are always some inaccurate bearings due to multi-path issues, and misalignment between bearing acquisition time and the position/heading of the car, but it works well enough to be able to allow navigation to the transmitter location. The display can get fairly busy, so there are options to threshold by signal quality, and to 'age out' bearings over time.

The beeping noise you hear in the video is the signal from the radio transmitter, in this case a 144.390 MHz beacon which transmits short CW 'pips'. We were listening to the signal with an Icom IC-705 attached to an omnidirectional antenna so we knew when the transmitter started and stopped (and hence when to trust any bearings produced by the DoA system).

Towards the end of the video you can see the HUD in action, with the blue lights showing the estimated signal arrival direction, relative to the front of the car. As I slowly drive past the transmitter location (which I could see out the side of the car), the bearings swing to the right, and the SNR shows as being very strong. This is exactly what the display was intended for - it's not about getting hyper-accurate bearings, but more knowing when you need to turn left/right, or get out of the car!

Thanks to Will Anthony for capturing the video while I was driving!

Software used:

AREG Fox-hunt Activities: https://www.areg.org.au/archives/category/activities/fox-hunting

Finding a Radio Fox using a Kerberos-SDR + ChaseMapper

KerberosSDR is our 4-channel phase coherent capable RTL-SDR unit that we previously crowdfunded back in 2018. With a 4-channel phase coherent RTL-SDR interesting applications like radio direction finding (RDF), passive radar and beam forming become possible. It can also be used as four separate RTL-SDRs for multichannel monitoring.

KerberosSDR is soon to be replaced with the upgraded KrakenSDR, which will begin crowd funding on Crowd Supply later this year. Be sure to sign up on the Crowd Supply page to be updated once the campaign releases as due to long supply chain crisis related lead times, only a limited amount of stock will be initially available.

Andreas Spiess Tracks Weather Balloons with a TTGO LoRa Board and RTL-SDR

Earlier in August we posted about radiosondy.info and the MySondy radiosonde receiver. Radiosondy.info is an internet service that aggregates radiosonde weather balloon data received and decoded by RTL-SDR users all over the world. MySondy is a cheap TTGO LoRa receiver that is modified with custom firmware and combined with a companion Android app in order to create a portable radiosonde receiver. A radiosonde is a small sensor and radio package normally attached to a weather balloon. Meteorological agencies around the world typically launch two balloons a day from several locations to gather data for weather prediction. With cheap hardware like an RTL-SDR and the right decoding software it is possible to receive weather and GPS data from the weather balloons launched in your area. 

Over on his popular YouTube channel, Andreas Spiess "the guy with the Swiss accent" has uploaded a video featuring the RadioSondy and the MySondy receiver projects. In the video Andreas first explains what a radiosonde is, and who launches them. He goes on to show the RadioSondy website and how to track balloons on it. He then shows the portable MySondy receiver for tracking radiosondes, before finally showing how to set up a permanent fixed ground station with RTL-SDR and Raspberry Pi for contributing to the RadioSondy aggregation website.

In amongst the demonstrations he also goes on several hunts for weather balloons that have landed near him, ultimately recovering two radiosondes and one intact balloon. The radiosondes were initially tracked with the RadioSondy fixed RTL-SDR ground stations, then when in the vicinity of the landed balloon pinpointed and found with the MySondy hardware.

#360 Tracking and Chasing Weather Balloons with TTGO LoRa board and Raspberry Pi. Fun and adventure

TechMinds: How to Track Weather Balloons Using SDR

In his latest video Tech Minds has uploaded a video showing how to use an SDR to receive transmissions from radiosondes carried by weather balloons. Every day meteorological agencies around the world launch weather balloons several times a day. Each balloon carries a device called a radiosonde which continuously transmits weather telemetry to a ground station. With an SDR, antenna and free software it's possible to decode these radiosonde signals yourself from home.

In the video Tech Minds uses an RSPdx, SDRuno, VBCable and the RS41 Tracker software to receive telemetry from an RS-41 radiosonde launched in his area. We note that an RTL-SDR and SDR# could also be used. He shows the various bits of weather information available from the telemetry including information like temperature, pressure, humidity and the dew point. GPS and hardware status data is also available. Finally he shows how to view the balloon's flight path in Google Earth.

How To Track Weather Balloons Using SDR

Tracking and Recovering A NWS Weather Balloon & Radiosonde with an RTL-SDR

Over on YouTube OLHZN High Altitude Balloons has posted a very entertaining video showing how to use an RTL-SDR and small grid dish antenna to track and recover a fallen weather balloon and its radiosonde. OLHZN writes:

The US National Weather Service (#NWS) launches over 200 weather balloons everyday carrying an LMS-6 #radiosonde / rawinsonde made by Lockheed Martin to an altitude of over 100,000 ft. and you can track & follow the flights from home and even find the landing site and pick them up! This is a fun #DIY project that you can do yourself from home and I'll show you how to do it here along with some tips so you can go find yourself a weather balloon & radiosonde!

How to track & recover a NWS weather balloon & radiosonde 🎈🎈 Ham Radio DIY

Aggregating Weather Balloon Data Online with a Custom Raspberry Pi Image

Thanks to a RTL-SDR.COM reader for submitting a tip about radiosondy.info, a weather balloon data aggregation website made by SQ6KXY. Weather balloons carry a sensor and transmitter payload called a radiosonde. These radiosondes transmit their data to a ground station via an RF signal, which is typically at around 400 - 406 MHz in most countries. With an RTL-SDR and decoder software (related tutorial) it is possible to receive and decode their weather data, and also often their GPS location data. The location data can be used to find and collect radiosondes once they reach the ground.

SQ6KXY has created a website called radiosondy.info which aims to aggregate and make weather balloon data received by contributors public. It is similar to sites like flightradar24 which aggregate ADS-B data from aircraft. The main page allows you to view radiosondes that are currently flying, and the archive of previous flights.

To make contributing to the site as simple as possible, SQ6KXY has created a custom image for the Raspberry Pi, which is automatically generated by the website for your particular user account, local radiosonde frequency requirements, and number of SDRs. They don't specifically mention it, but we assume that contributors are mostly using RTL-SDRs in their receivers. The custom image is available for generation after signing up.

Web tool to generate a custom Raspberry Pi Image for Radiosonde Tracking
Web tool to generate a custom Raspberry Pi Image for Radiosonde Tracking

Reprogramming Vaisala RS-41 Radiosondes to Transmit APRS, RTTY, CW in the Ham or ISM Bands

Radiosondes are light weight sensor packages that are attached to weather balloons. They transmit live RF weather telemetry down to earth as they rise. With an RTL-SDR and appropriate antenna it can be possible to decode this telemetry. One related hobby that a few people enjoy is radiosonde chasing, which is tracking and collecting radiosondes once they have fallen back to the earth. Some people collect them as trophies, and others like to repurpose them. For example in this previous post we've seen how some radiosondes can be repurposed into L-band antennas for RTL-SDR's.

Another way to repurpose radiosondes has recently been submitted to us by regular contributor 'happysat' who wrote in and let us know that it is actually possible to reprogram the commonly used Vaisala RS-41 radiosondes into being able to transmit ham radio APRS, RTTY or CW mode signals in the ISM or ham bands. The initial hack was first performed by SQ5RWU, and then OM3BC who managed to create easier to use software that could reflash the radiosondes internal firmware via the serial port on the radiosonde. This hack could be useful for any ham requiring a cheap transmitter for their own high altitude balloon experiments.

Happysat ended up testing this software with some RS-41 radiosondes that he had, and managed to receive some generated signals with an RTL-SDR of his. Some photos that he's submitted are shown at the end of this post.

In addition to the above, happysat also wanted to mention his other radiosonde re-purposing project which was turning a DFM-06 and DFM-09 into a functional GPS unit that could be used for navigation when connected to a laptop, or to sync time on PCs.

Transmit APRS
PE2BZ's Modded RS41 with Solar Panels
RS41 Programmer
Transmit APRS PE2BZ's Modded RS41 with Solar Panels RS41 Programmer

Wired Article about Radiosonde (Weather Balloon) Hunting

Wired.com has recently run a short article about Roland F5ZV's hobby of radiosonde hunting. A radiosonde is a small box containing electronic sensors that measure things like wind, temperature, humidity and also give out a GPS location. The radiosonde is carried into the upper atmosphere by a weather balloon, and these probes are usually launched twice a day in many locations around the world by meteorological agencies. The data is useful for weather forecasting and research.

The wired article discusses the hobby of radiosonde hunting, which is the sport of using radios to hunt and collect the radiosonde as it bursts and falls back to earth. He also writes how he was able to convince the Swiss Meteorological agency to allow him to attach a GoPro to a radiosonde which allowed him to capture some interesting images.

We'd like to remind readers that in many places in the world it is possible to receive and decode radiosonde data with an RTL-SDR, and we have a tutorial available here.

Radiosonde in flight captured by a GoPro camera.
Radiosonde in flight captured by a GoPro camera.

Tracking RS41-SGP weather balloons and reporting them to the APRS Network

Over on his blog Daniel Estevez has created a post showing how an RTL-SDR can be used to receive, plot and forward RS41-SGP radiosonde data to the APRS-IS network. Radiosondes are the small payloads used on weather balloons. They transmit weather and positional telemetry data back to a base station at the meteorological agency. But depending on the frequency used in your country it can be fairly easy to receive this data yourself with an RTL-SDR dongle and some decoding software. We have an introductory tutorial for radiosonde decoding available here.

In his area of Barajas, Spain the meteorological agency recently switched to the newer RS41-SGP radiosondes. To decode these Daniel uses the open source "RS" software which is capable of decoding various radiosondes including RS41. He notes that for now it is better to use his fork of "RS" as the base version contains a bug. He also shows how the received data can be plotted in Viking, which is a program used for plotting things like GPS tracks on a map.

Finally he shows how to feed the radiosonde data to the APRS-IS network. APRS is a packet radio system used by hams which works via radio and the internet, allowing for worldwide communication by radio. Feeding the data into APRS-IS allows anyone to see the flightpath on a site like aprs.fi.

Radiosonde Flight Path
RS41 Radiosonde Flight Path recorded by Daniel Estevez