Project Horus – Telemetry Test Flight #2 (Horus 51) Flight Report

Today’s telemetry test flight (now designated as Horus 51) was performed with (mostly) good results! This launch was an experiment to investigate solutions to the ‘Horus Binary’ payload PLL-loss-of-lock issue that has been observed on previous launches. Three payloads were launched, with variations on insulation and transmit power, all using reprogrammed Vaisala RS41 radiosonde PCBs. As a result, there was a lot of telemetry to receive on this flight!

Getting ready to launch the payloads

The launch was a fairly relaxed affair, with only a small launch crew on-site. Launch occurred right on time at 11AM. It was quickly discovered that a bit too much helium was used (dodgy gas flow-rate meter!), and so the ascent rate was higher than expected resulting in the small balloon used bursting at 16.2km altitude.

Horus 51 Flight Path

As the pre-launch flight path prediction had the landing area somewhere south-west of Loxton, none of the launch crew attempted to chase this launch. Instead, Ivan (VK5HS) from the Riverland Radio Club lead a small team (Ivan, David and Peter) out from Renmark to recover the payload. As it turns out, the higher ascent rate and lower burst altitude resulted in the landing location being further away from Loxton than expected, but the Riverland boys were able to track payloads down to the ground and easily recover them not long after landing.

David (left) and Peter (right) with the recovered payloads.

Many thanks to Ivan & Co for making the effort to get out and chase, it is much appreciated!

Horus 51 - Flight Statistics

MetricResult
Flight Designation:Horus 51 - Telemetry Test Flight #2
Launch Date:2018-11-25 00:30 UTC
Landing Date:2018-11-25 01:40 UTC
Flight Duration:1 Hour 10 Minutes
Launch Site:-35.07568, 138.85701
Landing Site:-34.68642,139.92380
Distance Traveled:106 km
Maximum Altitude:16,201 m

Telemetry Statistics

Thanks to all who participated in the launch by receiving telemetry from one (or more!) of the three payloads. Statistics on how much telemetry was contributed by each receiver callsign is below:

Horus 51 - HORUSBINARY (434.640 MHz) Receiver Statistics

CallsignReceived PacketsPercentage of Flight ReceivedFirst-Received Altitude (m)Last-Received Altitude (m)
VK5FAAP403.7%49152951
VK5HS29226.9%1283660
VK5KX-3100892.7%632125
VK5NEX33530.8%148634601
VK5QI-951647.5%340142
VK5ST-489382.2%23741301
VK5WTF20.2%39593969
YOUR_CALL_HERE47844.0%2339296

Horus 51 - HORUSBINARY2 (434.650 MHz) Receiver Statistics

CallsignReceived PacketsPercentage of Flight ReceivedFirst-Received Altitude (m)Last-Received Altitude (m)
VK5APR11717.7%9053849
VK5FJGM26740.3%339410661
VK5KJP54682.5%20541313
VK5KX-264196.8%763103
VK5LJG46670.4%12754751
VK5LJG-940861.6%3641809
VK5NEX39659.8%290714293
VK5QI-964497.3%378103
VK5ST-253681.0%2248893
YOUR_CALL_HERE31447.4%298114293
vk5mad38558.2%146414293

Horus 51 - 4FSKTEST (434.660 MHz) Receiver Statistics

CallsignReceived PacketsPercentage of Flight ReceivedFirst-Received Altitude (m)Last-Received Altitude (m)
VK5APR78475.0%40513538
VK5DSP11611.1%926512591
VK5KX-2121.1%1515115449
VK5QI-961658.9%340144
VK5ST-188184.3%24041246
VK5WTF80877.3%601395

Please make sure you follow the configuration instructions when using the Horus Binary decoder, to avoid the ‘YOUR_CALL_HERE’ entries seen in the above tables!

Payload Testing Results

Previous Horus launches have seen the repurposed Vaisala RS41 payloads lose PLL-lock mid-flight, with the transmit frequency drifting up the 70cm band as temperature decreases. Testing on the ground indicated this may be due to the Radio IC (a Silicon Laboratories Si4032 FSK transmitter) failing with the low temperatures experienced during flight. The fact that the the RS41 sondes do not usually fail during their intended application pointed at the lower transmit power (25mW vs 50mW) used on Horus flights being a possible factor.

On previous flights the following results were seen:

  • Horus 49 (Anstey 2.0) – RS41 Foam Only, 25mW – No issues Encountered.
  • Telemetry Test Flight #1 – RS41 Foam Only, 25mw – Failed on Ascent at 9km altitude, recovered on descent at 1km altitude.
  • Horus 50 – Stock RS41, 25mW – Failed on descent for ~6 minutes between 13km and 9km altitude.

With 2 failures and one success, it was decided that more data needed to be gathered.

Foam-Only (Left), ‘Stock’ RS41 (Middle), Custom Enclosure (Right)

On this launch, two payloads were operated at 50mW transmit power, one with a ‘stock’ enclosure (‘HORUSBINARY’) and one with only the inner foam insulation (‘HORUSBINARY2’). Using only the inner foam insulation provides a significant weight reduction, cutting the payload weight almost in half (~120g to ~60g).

A third payload (‘4FSKTEST’), using a custom-built foam enclosure was also tested, transmitting at 25mW. This had a similar overall weight (66g) to the foam-only RS41 enclosure, and re-flew the RS41 board that failed on Horus 50.

A bug in the firmware, discovered after the Horus 50 flight, was also fixed for this launch. This fix allowed gathering of measurements from a temperature sensor on the silicon die of the radio transmitter IC – unfortunately the temperature measurements captured on previous launches are invalidated as a result of this bug.

Horus 51 Payload Temperatures

Sadly, the foam-only payload (‘HORUSBINARY2’) was observed to fail at 14.3km altitude during ascent, and recover at 4.8km on descent, failing with a radio IC temperature of 0 ˚C.

Failure of the HORUSBINARY2 payload, as observed by Joe VK5EI

Both the stock RS41 and custom enclosure payload remained operational throughout the flight. The overall higher temperatures reported by the Stock RS41 payload may be a result of a bias in the temperature sensor, or may be a result of the better insulation – Further investigation will be performed once the payloads make their way back to Adelaide.

Curiously, the two other payloads reported radio IC temperatures lower than the failure point of the foam-only payload (0˚C), indicating that perhaps it is not the radio IC at fault, but another component on the PCB. Further investigation will be performed on RS41 PCBs using selective cooling of components, prior to the next Horus launch sometime in January 2019.

However, based on the results from this flight, it appears that the safest option for the moment is the Stock RS41 enclosure, transmitting at 50mW. As always, Horus flights use  redundant telemetry transmitters, so that a failure of a single transmitter does not compromise our ability to track and recover!

Project Horus – Telemetry Test Flight #2 – Sunday 25th November 11AM CDST

UPDATE: Predictions look good, so this flight will be going ahead as planned. The launch team will not be chasing this flight – others are welcome to chase/recover the payloads if they wish.

Current planned flight parameters (for prediction purposes) are a 4m/s ascent rate, 20km burst altitude, and a ~7m/s descent rate.

 

On Sunday, the 25th of November, Project Horus will be performing a small balloon launch from Mt Barker High School Oval, at approximately 11AM CDST. Live flight tracking will be available on the HabHub online tracker as usual. A guide on how to decode the new Horus binary telemetry mode is available here.

This launch is another test flight of the new ‘Horus Binary’ telemetry payload, which uses a new modulation mode developed by David Rowe VK5DGR and Mark Jessop VK5QI with 6dB better performance than the usual RTTY telemetry. This telemetry mode has been flown on a few recent Project Horus flights, with mixed success – The modem has performed flawlessly, the payloads themselves not so much! These flights have flown reprogrammed Vaisala RS41 radiosondes, which while working perfectly on Bureau of Meteorology launches, have proven troublesome on Horus launches!

Drifty Horus Binary Payload – Hopefully not on this this flight!

The last telemetry test flight suffered a loss of PLL lock on ascent, believed to be due to temperature issues, causing the payload to drift right up the 70cm band. On Horus 50, a similar fault occurred on descent, though the payload recovered within a few minutes. Further investigations confirmed a temperature issue, likely due to the lower transmit powers used on Horus flights (25mW) compared with the stock transmit power of 50mW.

This flight aims to test a few different variations on the payload flown on Horus 50, to determine if transmitting at a higher power keeps the payload alive. A few different modifications to the payload insulation will also be tested.

Currently we plan to fly 3 telemetry payloads (all on USB, +/- temperature drift):

  • 434.640 MHz – Callsign ‘HORUSBINARY’ – Unmodified RS41, 50mW TX power.
  • 434.650 MHz – Callsign ‘HORUSBINARY2’ – RS41 without outer plastic shell, 50mW TX power. Prioritise reception of this payload.
  • 434.660 MHz – Callsign ‘4FSKTEST’ – RS41 PCB in custom enclosure, 25mW TX power.

The Horus Binary uploader script will automatically determine the payload callsign as long as you are running a recent version. Please make sure you have updated to the latest version (2018-11-15) of the Horus Binary uploader before this flight, otherwise the HORUSBINARY2 payload will not be recognised, and data for the other payloads may be corrupted. Those who were set up for Horus 50 can simply download the latest payload ID list, and place it in their horusbinary directory.

Launch will be from the usual Mt Barker High School Oval site, and launch teams will be on-site around 10:15AM, for a 11AM launch. All are welcome!

AREG’s 20th Anniversary Event – Horus 50 Balloon Launch – 4th November 2018

2018 marks 20 years since the Amateur Radio Experimenters Group was formed. To celebrate this milestone, the club is planning to fly a special Amateur Radio focused high altitude balloon in what will be the 50th Project Horus Mission.

The Project Horus team itself is also celebrating 8 years in the air! Project Horus was founded by Terry Baume and continues to perform regular high-altitude balloon launches from locations around South Australia under the auspices of the Amateur Radio Experimenters Group.

When will this be happening? Currently it is planned to fly on Sunday the 4th of November (weather permitting). Liftoff is planned for 10AM ACDT. We are going for altitude so coverage will hopefully extend as far as Melbourne at the peak of the flight.

The goal is to engage with amateur radio in as many ways as possible. We want you to talk through the balloon, see the world from the balloon’s perspective and know where the balloon is during the flight! How can you do all this you might ask? The Project Horus team have specifically tailored this flight to include:

  • a 2m (down) / 70cm (up) Cross-band FM repeater. Amateurs within the repeater footprint will be able to make live QSOs with the club station VK5ARG and each other via the FM repeater using relatively modest stations.
  • a 2m SSTV beacon transmitting images from the balloon live during the flight. You will be able to see the world from the balloon’s perspective using a 2m receiver and simple software (you can even use an app on your phone).
  • Track the balloon via a 2m APRS beacon during the flight!

The launch site will be the usual Mt Barker High School Oval. Launch crews should be on-site around 8:30-9AM. If you haven’t attended one of our launches before, this is a great opportunity to come along and see what’s involved first-hand!

As usual, there’s always the chance the weather for the planned launch date may not be suitable, so a backup launch date of Sunday the 18th of November has been tentatively penciled in (the 11th being the AHARS buy & sell weekend).

Cross-band FM Repeater

Likely suspects operating the cross-band repeater on Horus 23

The cross-band repeater will be using the following frequencies:

  • Uplink: 438.900 MHz, with a 123 Hz CTCSS tone required for activation.
  • Downlink: 147.500 MHz  (~1.4W output power).

To transmit to the balloon at the maximum range of 700km (once the balloon reaches >30km) you will need approximately 10-30W and an 10dBi gain antenna and a clear takeoff towards the balloon. Those stations closer to the launch site will be able to get away with much less.

PLEASE MAKE SURE YOU can hear the repeater before transmitting
and remember to make sure you SET YOUR CTCSS TO 123Hz
or you will not access the repeater.

As with previous flights, the repeater will be run as a controlled net. Listen for VK5ARG acting as net control and please follow their instructions so that as many people as possible can share the repeater.

FM-SSTV Imagery Payload

Instead of the usual Wenet imagery payload this launch will have a new SSTV transmitter operating on 145.100 MHz FM. It will run approximately 250mW transmit power. The transmitter will have 30 second gaps between image transmissions to avoid overheating the transmitter.

Scottie 2 SSTV Imagery Example

The payload will be transmitting images using the Scottie 2 SSTV mode throughout the flight, and can be decoded using any SSTV software capable of decoding this mode (pretty much all of them!). This is a mode that typically is used on HF but is equally adapted to VHF FM work. (Note it is not the same as the PD120 transmissions from ISS).

Examples of suitable software you can use to decode the SSTV pictures include:

Any FM receiver (including handhelds) should be capable of receiving this payload, though as with the cross-band repeater, a Yagi antenna may be necessary for reliable reception at the edges of the transmitter footprint.

If you do receive images, please post them to Social Media and on Twitter include the #horus50 hashtag so everyone can see them!

Telemetry Payloads

As always, we’ll be flying the usual assortment of telemetry payloads, including:

  • Our usual 100 baud 7N2 RTTY telemetry on 434.650 MHz USB. This can be decoded using dl-fldigi, with a reception guide available hereNOTE: There is a known issue with dl-fldigi where it does not upload any received telemetry until about 10 minutes after the software is started. Any telemetry received in this time period will be queued and uploaded after the startup period has completed (i.e. no telemetry will be lost).
  • 4FSK Telemetry decoder

    The new 4FSK Binary telemetry will be transmitting on 434.640 MHz USB. This uses a separate decoder, with setup instructions for this available here. (Previous listeners note that there have been updates to the software – please re-download the latest version!). We would love reports of how the 4FSK signal compares to standard RTTY!

  • If weight permits, there will be an APRS beacon operating on 145.175 MHz with the callsign VK5ARG-12. This will be received automatically by the APRS network.
Tracking of the flight will be available on the HabHub Tracker, available at this link. (Note that other balloon launches will also be visible on this page, including the Bureau of Meteorology launches from Adelaide Airport).
Follow the #horus50 hashtag on Twitter for updates from the launch and chase teams on the launch day.
Stay tuned for updates closer to the launch date…
73
Mark VK5QI

Horus Telemetry Test Flight 29th July 2018 – Flight Report

With all the successful flights that Project Horus has had recently, I guess it’s about time we had one that didn’t quite go to plan…

Windy conditions at the launch site made filling difficult

First up – the weather. If this was a full-size Project Horus launch, we would have likely cancelled and re-scheduled the flight. However, since this was just a small test flight with a disposable payload, we decided to have a go.

Thankfully we didn’t experience the forecast showers, however 30-40kph winds at the launch site made filling an exciting experience, with the balloon blown all over the place. Mark VK5QI, Will VK5AHV, Chris VK5FR and Matt VK5HZ were the launch crew for the morning. Graham VK5GH also made an appearance. Just as we were starting to tie off the balloon a wind gust came up and tore the balloon off the fillter… goodbye balloon! (Memories of Horus 8, though this time without the garage to stop the balloon flying away).

Bye bye balloon… (Photo courtesy Matt VK5HZ)

There was just enough gas left in the cylinder to fill a small ‘backup’ balloon (a 100g Hwoyee) and get enough lift to get the payload in the air.

The achieved ascent rate after launch was ~3m/s, a bit lower than the planned 5m/s, however with the switch to a smaller balloon, this actually resulted in a fairly similar flight path to what was originally planned.

The first part of the flight went pretty normally. Many receiving stations came online to decode the new 4FSK Horus Binary mode, including a few new callsigns. Will VK5AHV and Mark VK5QI headed off towards Bear Rock to track the payload as long as possible, while Marcus VK5WTF was already stationed up on Accomodation Hill to do the same. Ivan VK5HS and Peter VK5PE were already out in the expected landing area (South of Loxton), recovering the morning’s Bureau of Meteorology radiosonde launch.

Faulty payload!

At just about 9km altitude… something went wrong in the payload. The signal became very wide, and then immediately started drifting up the band. The current theory is that the payload flew through a cloud on ascent, and a combination of condensation within the payload and extreme cold caused some problem with the radio IC. UPDATE: Testing has confirmed that the issue was related to insufficient insulation around the radio IC. Better sealing around the payload edges solves the issue, and hopefully this won’t occur on future flights.

The transmitted signal continued to drift up through the 70cm band, topping out at about 436.4 MHz before descending back down again. At some point (estimated to be about 21km altitude) the balloon burst, sending the payload quickly back towards the ground.

As we watched the signal drifting back down the band, we wondered – what will happen when it gets back to the original frequency – 434.640 MHz? Sure enough, as the frequency drifted closer towards 434.640 MHz, the drift rate sped up, and it almost ‘snapped’ back into place – and the 4FSK started up again! (Later analysis of the telemetry showed that the GPS & micro-controller continued operating while the radio went walkabout.)

Quickly we rushed to get the decoder up and running again, to find the payload was at ~1km altitude and dropping fast. From Bear Rock we were able to decode the payload down to ~300m (at a distance of 140km, not bad!). Peter VK5PE’s home station in Renmark was able to track it down a bit further, to ~220m.

Ivan and Pete turned around (they were halfway back to Renmark) and were able to recover the payload not far from the last reported position.

Peter VK5PE with the payload in hand!

Even with the issues this flight, we still met the primary goal of getting stations decoding the new Horus Binary telemetry mode. Stations seen to upload telemetry included:

VK5APR, VK5EI, VK5FJGM, VK5FLJG, VK5KJP, VK5KX, VK5NEX, VK5PE, VK5QI, VK5ST, VK5TRM, VK5WTF, and ‘AUSMEZ’

Thanks to all for your participation! We will be evaluating the received data and working out better ways of weatherproofing the modified RS41 payloads to avoid the issues encountered on this flight. Expect to see the Horus Binary telemetry on future flights!

Horus Telemetry Test Launch – Sunday 29th July 11AM CST

UPDATE: Unfortunately the payload failed at approximately 9km altitude. It recovered on descent just prior to landing, and we were able to get a landing location. Ivan VK5HS and Peter VK5PE were able to recover the payload from the middle of a large field south of Loxton.

Thanks to all that decoded the initial part of the flight. If you could please e-mail your log files through as mentioned below that would be appreciated.

This coming Sunday, the 29th of July, Project Horus will be performing a small balloon launch from Mt Barker High School Oval, at approximately 11AM CST. Live flight tracking will be available on the HabHub online tracker as usual.

This launch is another test flight of the new ‘Horus Binary’ telemetry payload, which uses a new modulation mode developed by David Rowe VK5DGR and Mark Jessop VK5QI with 6dB better performance than the usual RTTY telemetry. The first flight of this new payload was on the Horus 49 (Anstey 2.0) flight, where it performed well!

A modified Vaisala RS41, which transmits the new Horus Binary telemetry

The aim of this flight is to provide another opportunity for listeners to attempt decoding of this mode. Like the RTTY telemetry, the Horus Binary telemetry can be received using a 70cm Single-Sideband receiver. Telemetry will be on 434.640 MHz USB (+/- temperature drift). This will be the only payload on this flight, and we are not intending on recovering the payload (though others are welcome to go after it!).

Decoding of the the new mode is not supported in dl-fldigi, and hence new software must be installed – a guide on how to install and run the required Horus Binary decoder software is available here.  (A note to those listeners that decoded the binary payload on Horus 49: a few new features have been added to the Habitat uploader utility – please update to the latest version!)

To help debug some issues that were encountered on the last flight, it would be appreciated if all listeners e-mailed the ‘telemetry.log’ and ‘horusb_debug.log’ log files (created by the horusbinary uploader) through to Mark VK5QI (vk5qi@rfhead.net) at the conclusion of the flight.

 

Horus 49 – Anstey in Space v2.0 – Success!

On Sunday the 8th July, the Tea Tree Gully Library’s echidna mascot, Anstey, rose into the sky to an altitude of 36,374 metres under a High-Altitude Balloon. This was Anstey’s second flight into the stratosphere, and Project Horus’s 49th balloon launch.

Originally planned for the 30th of June, Horus 49 had to be delayed a week due to very poor weather conditions. Even still, this flight was a a long one for the chase teams! Fortunately we had the assistance of a team from the Riverland Radio Club who mobilized from their home base (much closer to the LZ) and who then played a big part in tracking and retrieving Anstey at the end of his flight. You can read about their adventure on the RRC Blog.

Launch Activities

As usual, the launch was from the Mt Barker High School oval – thanks must go to the school for allow us to use their oval for so many launches! A good number of AREG club members came along to help out with the launch. Also present at the launch were members of Anstey’s Space Club, there to watch the launch and see Anstey off into the stratosphere!

Filling the balloon.

Payloads were laid out, turned on and tested, and the balloon was filled with somewhat more gas than usual. The flight path predictions had a possible risk of landing close to Loxton, so additional gas was used to give a higher ascent rate (as it turned out, a *very* high ascent rate). Wind gusts made filling the balloon a bit of a challenge, but there were no lack of hands to help keep things from getting out of control.

At just after 10AM, the wind died down and we had a perfect launch!

Launch of Horus 49

The Flight

On board Anstey had two cameras recording things. The first was a GoPro miniature video camera! The second was a still camera that was sending photos live to ground as the flight progressed.

Chase & Recovery

Right after the launch, Mark VK5QI and Will VK5AHV quickly headed off towards the expected landing area to the South-West of Loxton – a long drive away! Marcus VK5WTF and partner were also following not far behind.

The ascent rate ended up being much higher than intended – ascent rates as high as 9m/s were observed at some points in the flight, resulting in a shorter than expected flight. Even still, the Hwoyee 1600g balloon used made it to a very respectable 36374 metres altitude before bursting.

With the original flight path prediction due to land near Loxton, it was looking pretty unlikely that the chase teams departing from Mt Barker would make it there before landing. Luckily, a group of Riverland Radio Club members were on the case! Ivan VK5HS, Peter VK5PE, Danny VK5DW and Andy VK5LA also headed out to chase, starting from the Loxton area. Rob VK5TRM was also out for the chase. Ivan & co had been practicing by hunting the Bureau of Meteorology radiosondes, so were well experienced in chasing balloons – so much so that they were able to get into position to watch the balloon land in an area of scrubland near the locality of Mantung (40km SW of Loxton).

Mark and Will were not far behind, arriving at the landing site a few minutes later. A short walk later and Anstey was sighted… about 8 metres up a gum tree!

With some persuasion from a SpiderBeam pole, Anstey was recovered. Many thanks to all those who came along for the chase!

Horus 49 Recovery Team

Live Wenet Imagery

Throughout the flight Anstey was imaged via a version of Project Horus’s ‘Wenet’ imagery payload, which transmits images down to the ground via a 115kbps 70cm transmitter. As expected the images of Anstey were amazing, and were viewable live via HabHub’s SSDV webpage.

This live imagery is only possible through volunteers running ground-stations. Thanks go to VK5APR, VK5EU, and VK5KX who ran stationary receivers. Mark VK5QI was also running a mobile Wenet receiver in his chase car.

CallsignPackets ReceivedTotal Data Received (MB)
VK5KX23846058.22
VK5QI (Mobile)21801253.23
VK5APR21304552.01
VK5EU15317537.40

Telemetry – RTTY & Horus Binary

As with all previous Project Hours flights, a RTTY payload was flown. Many listeners contributed to tracking this payload:

CallsignPackets HeardPercentage of Flight HeardPayload Alt at First RX (metres)Payload Alt at Last RX (metres)
VK5EI103393.4%3962695
VK5EU101792.0%7012780
VK5FAAP98288.8%16373203
VK5FJGM73966.8%11229329
VK5FLJG62656.6%22117751
VK5KX95586.3%1680193
VK5NEX91282.5%26335108
VK5ST83375.3%28783897
VK5ZAR79371.7%12055551

New to this flight was an experimental ‘Horus Binary’ payload, which was transmitting a MFSK telemetry mode developed by David Rowe VK5DGR and Mark Jessop VK5QI. This new mode has significant performance advantages over RTTY, and will hopefully become the new default telemetry system for Project Horus flights. David VK5DGR also has an overview of the payload and how it performed on the flight on his blog. Many stations were able to run the new decoding software and track the flight using this mode:

CallsignPackets HeardPercentage of Flight HeardPayload Alt at First RX (metres)Payload Alt at Last RX (metres)
VK5AKH/KX/ZM (Portable)151182.4%6970101
VK5APR154184.0%26314850
VK5FJGM123467.3%76925875
VK5FLJG157786.0%6755217
VK5FTAZ83245.4%91466484
VK5IX149181.3%818661
VK5KJP147180.2%27484404
VK5RR28815.7%33826400
VK5ST166390.7%24351286
VK5TRM171993.7%1854139
VK5QI (Mobile)156085.1%34364
VK5WTF (Mobile)103956.7%2776139

The new mode provides position updates twice as fast as the 100 baud RTTY payload, and with 6dB better decoding performance (meaning double the range!). The update rate may have been too fast it seems – while about 2600 packets were transmitted during the flight (confirmed as received on VK5QI’s mobile station), only ~1800 of these made it into the Habitat tracking database! This is likely a result of upload timeouts – some changes will be made to the software prior to the next Horus Binary flight so this issue can be further debugged. Still, the new mode performed incredibly well in the chase cars, providing  rapid and regular updates to the chase car mapping systems.

Thanks again to all who helped track the flight using both Wenet, RTTY, and the new modem. Expect the Horus Binary mode to make appearances on more flights in the future!

Upcoming Launches

To give more listeners an opportunity to decode the new Horus Binary mode (and to use up some leftover gas from Horus 49!), a small balloon launch will take place sometime in Late July. This will be a ‘small’ balloon launch (as per the CASR Part 101.E definition), flying a re-purposed RS41 radiosonde clocking in at just over 40 grams. A new version of the Horus Binary decoder will be released prior to this launch to allow better analysis of the upload issue encountered on Horus 49.

Also coming up is the 20th anniversary of AREG – as part of the celebrations, we will be performing Project Horus’s 50th launch! On this flight we expect to fly:

  • A 2m/70cm Cross-Band repeater, similar to what was flown at the WIA AGM launch.
  • A SSTV transmitter, sending images in the PD120 SSTV mode.
  • An APRS beacon (depending on weight budget)

.. along with the usual telemetry and cutdown payloads. Stay tuned!

Horus 49 – Anstey in Space – NEW DATE CONFIRMED

UPDATE: Anstey was successfully launched to a height of 36374 metres, followed by a landing in the Murray Mallee and a recovery by AREG and Riverland Radio Club members. A full write-up of the launch will be posted in the next few days.

Anstey at 36km Altitude on Horus 49!

Back in 2016, AREG & Project Horus helped Anstey the Echidna, the Tea Tree Gully Library’s mascot, explore near-space. Anstey didn’t have enough fun on the previous launch, and so on the 8th of July 2018, we will be re-launching Anstey back into near-space on a high-altitude balloon launch!

Anstey in near-space on Horus 39

The launch is currently scheduled for 10AM CST on Sunday the 8th July, however as usual, weather conditions may cause this to be re-scheduled. The launch will be from the Mt Barker High School Oval, and spectators are welcome. Launch crew should be on-site from approximately 9AM.

Tracking of the flight will be available via the HabHub tracker.

Telemetry Information

The telemetry frequencies for the flight are as follows:

  • RTTY Telemetry – ‘HORUS’ – 434.650 MHz  (100 baud, 425 Hz Shift, 7N2)
  • Wenet Imagery – 441.200 MHz (Wenet 115kbps FSK)
  • Experimental Horus Binary Payload – 434.640 MHz (100 baud 4FSK)

As usual, the RTTY telemetry can be decoded using dl-fldigi.


Note: Recent testing of dl-fldigi’s decode performance has found that the auto-configured RTTY receive bandwidth is too narrow, and can detrimentally impact decode performance (by up to 3dB!).

To fix this, open dl-fldigi, and in the Configure menu, select Modems, and then go to the ‘RTTY’ tab. Drag the ‘Receive filter bandwidth’ slider to 200, then click ‘Save’. Note that this setting will be reset whenever you hit the ‘Auto-Configure’ button!


Wenet Imagery

As with most Project Horus launches, this flight will feature live imagery via the Wenet high-speed imagery downlink. Images will be available throughout the flight at this link:

http://ssdv.habhub.org/HORUS

Reception of the Wenet signal requires a RTLSDR and a Linux PC/Laptop. Instructions on how to set up the required software are available here.

Experimental 4FSK Telemetry

This launch will include the use of a re-purposed Vaisala RS41 radiosonde, programmed to transmit a new binary 4FSK telemetry mode, developed by David VK5DGR and Mark VK5QI. This new mode is intended to eventually (read: probably a year away) replace RTTY telemetry on Horus flights. It runs at 100 baud, is approximately 850 Hz in bandwidth, and has an almost 6dB performance improvement over the current RTTY telemetry! 

Decoding this telemetry requires installation of a new decoder application (an updated version of FreeDV), and some helper scripts to upload the data to the online tracker. A guide on how to install and operate this new decoder is available here.

Conclusion

More information will be available closer to the flight!

High Altitude Ballooning: Horus 48 – Flight Report

At 10:08AM CDST, on the 11th of March 2018, Horus 48 was launched from Mt Barker.

This planning for this flight started out as an excuse to use up some helium leftover from the previous two launches, and quickly evolved into a mechanism for testing out some new payloads and launch concepts – the main one being the use of the ‘THOR16‘ data mode, which is considerably more robust to interference than RTTY, at the cost of being about 50% slower.

Horus 48 Payloads

Horus 48 Payloads

As we only had a limited amount of leftover helium available (~1.6m^3), the mass of the payloads had to be kept to an absolute minimum. New foam payload boxes were built with this in mind, with the new THOR16 and RTTY payloads weighing in around 70g each. (Thanks to Peter VK5KX for supplying the antenna wire!)

The week prior to the launch, a ‘test and tune day’ was conducted. An example THOR16 signal was broadcast from Mt Lofty summit, with many stations tuning in and decoding telemetry. The responses from this test were promising, with one station reporting he had much more success with THOR with it’s forward-error-correction, as local LIPD noise would disrupt RTTY decoding resulting in invalid telemetry.

Thanks to the following stations who participated – it was great to see so much interest!

VK5FJGM VK5ZAR VK5KJP VK5KIK VK5FTAZ VK5APR VK5NIG VK5NG VK5KX VK5AKK & VK5OI

Launch Preparation

The launch was quite light-on with helpers – Mark VK5QI and Will VK5AHV performed the launch activities, with help from David VK5DGR, Drew VK5XFG, Rod VK5ZOT and a few others.

The original intention to use a small 100g balloon went out the window the night before the launch, when it was discovered the specified burst diameter for the 100g balloon was not quite as expected – this would have resulted in a ~3km burst altitude! Instead an old 1000g Hwoyee balloon was used. The larger balloon meant all the gas in the cylinder had to be used up, and even this only resulted in an ascent rate of 2.5m/s (we usually aim for 5m/s).

To counter the low ascent rate, which would have resulted in a 4 hour long flight, and a landing well to the east of Bowhill, one of the Horus cutdown payloads was flown, allowing termination of the flight via a command from the ground. This cutdown payload used a newly developed cutdown device (to be kept under wraps for now!), which is intended to replace the nichrome wire string-cutter device previously used – Experiment #2 for this flight!

All up, the payloads combined only weighed ~300g. The smallest parachute we have in stock was used (a 2ft ‘Rocketman’), and was hung off the side of the balloon train instead of in-line with the payloads as we would usually do. This was to try and reduce the tangling of the parachute with the payload string that had been encountered on the last few flights – Experiment #3!

Launch & Chase

 

Launch was pretty much textbook – some light winds encountered during filling died down for an easy release into the skies. Will and Mark immediately headed off towards the target landing area, while David VK5DGR and co headed off to Mannum for a bakery stop.

At about 10km altitude the cutdown signal was sent to the payload, with the intent of landing the payload to the south-east of Mannum. The new cutdown device worked first-go – a success for Experiment #2! The payloads then quickly descended to a landing on a property just across the river from Port Mannum.

Will and Mark caught sight of the payloads at about 800m altitude, and were able to watch the payloads descending behind a hill, into an empty field. The parachute was clearly doing its job, and was not tangled up or ensnared in the other payloads – another successful experiment!

A quick discussion with the landowners (and their friendly dogs) and permission to enter the field and retrieve the payloads was granted. A short walk and the payloads were in hand!

Flight Statistics

Everything is more interesting with data – so here is the flight’s vital statistics.

MetricResult
Flight Designation:Horus 48 - THOR16 Test Flight
Launch Date:2018-03-10 23:38 UTC
Landing Date:2018-03-11 01:16 UTC
Flight Duration:1 Hour 37 Minutes
Launch Site:-35.07568, 138.85701
Landing Site:-34.93807, 139.31944
Distance Traveled:44 km
Maximum Altitude:10,187 m
Horus 48 Flight Path

Horus 48 Flight Path

New Telemetry System Performance

Even with a 10.2km maximum altitude, many receiver stations around the state were able to decode both the THOR16 and RTTY telemetry:

RTTY Telemetry Scoreboard
CallsignPackets HeardPercentage of Flight HeardPayload Alt at First RX (metres)Payload Alt at Last RX (metres)
VK5APR60.7%13921465
VK5DSP687.9%52556203
VK5EU78190.8%7571454
VK5FJGM/M18521.5%56048306
VK5HS44651.9%38783414
VK5KFB30335.2%58285649
VK5KIK586.7%27413749
VK5KJP64875.3%12443210
VK5KX-0177289.8%771163
VK5NG111.3%46724804
VK5OI15417.9%22656506
VK5QI-971282.8%35722
VK5TRM70.8%24981782
VK5ZAR26330.6%73035162
VK5ZM49057.0%2339163
VK5ST62372.4%31711260
VK5ZAI69480.7%18161843
THOR Telemetry Scoreboard
CallsignPackets HeardPercentage of Flight HeardPayload Alt at First RX (metres)Payload Alt at Last RX (metres)
VK5AKK27093.1%621903
VK5APR22979.0%9682688
VK5DSP16055.2%22283591
VK5EI27594.8%6211602
VK5FAAP22979.0%18251840
VK5FJGM/M12944.5%36301602
VK5HS10435.9%56432688
VK5KIK12743.8%8081132
VK5KX-0225889.0%1331307
VK5NEX23681.4%12172445
VK5NG17861.4%4853903
VK5NIG5619.3%14209863
VK5OI19165.9%7442325
VK5QI-913947.9%36231
VK5RR11840.7%60184988
VK5ST19968.6%33121840
VK5TRM3712.8%91187969
VK5ZAR15252.4%8612206
VK5ZEA13747.2%51186667

The callsign pie chart shows the combined result of both RTTY and THOR telemetry streams – great to see so many contributors this time!

So, was the THOR16 telemetry useful? It’s hard to tell with just one launch. From the chase-car, the following observations were noted:

  • The slow speed of THOR16 (one update every ~20 seconds) makes tracking the flight through critical stages like burst and descent difficult. The chase team ended up switching to the cutdown payload telemetry (updates every 5 seconds) to get more frequent position updates.
  • THOR16 was quite robust to mobile fading, however,
  • … fldigi has no automatic frequency correction for THOR16. While the payload’s transmitter didn’t drift very far, it did drift far enough for the performance of the demodulator to drop, resulting in quite a few lost packets until the issue was noticed.

Since the THOR16 payload is so light (only 65 grams) you can expect to see it on more upcoming flights – please continue to send in reports on how it compares to the RTTY payload!

Thanks again to all listeners who decoded data from the flight, including those who went portable to track the payload down to the ground (VK5KX, VK5ZM & VK5GR).

RTTY as received at VK5KX

THOR16 as received at VK5KX

Addendum: HabHub Tracker Issues

Some listeners noted issues with the Tracker where the payload list on the left side of the webpage did not populate. This is a known bug and is currently being worked on. The bug is related to window sizes, so if you re-size your browser window slightly it should re-draw the web-page, and the payload list should appear.