LoRa LoRa Laughs!

Due to the restrictions on airborne amateur radio operation in the UK High Altitude Balloon (HAB) enthusiasts have been forced to utilise licence exempt low power devices in novel ways to make radio trackers for their payloads. I have written plenty on this blog about my HAB tracking, the UKHAS distributed listener network and my own flights.

Until recently the preferred method was to use RTTY transmissions, however the advent of the IoT (Internet Of Things) has seen manufacturers of radio modules develop devices to increase both the range and reliability of communication between ‘connected’ embedded devices.

One such development are LoRa devices, primarily for devices to connect to a global wide-area network LoRaWAN, more information can be found at the LoRa Alliance in addition there are some open hobbyist networks such as The Things Network using these devices.

Using chirp spread-spectrum modulation these LoRa devices are marketed as being capable of robust, interference and fade resistant communication over longer distances and higher data rates.

The UK HAB community has begun experimenting with these devices and one of their keen proponents is Dave Akerman (M0RPI). Dave has developed both payload software for the “Pi In The Sky” PITS tracker along with Anthony Stirk (M0UPU) and gateway software in collaboration with Robert Harrison M0RJX. The ‘gateway’ is the necessary receiver element to upload the data to the tracking system. (all software is on the PITS Github page)

Dave gave an informative presentation on LoRa at the UKHAS 2016 Conference which is now available online (starts around 3 minutes in)

I had intended to fly a LoRa transmitter on my 2015 Hamfest balloon but it stopped working at the eleventh hour and hadn’t done anything else with LoRa till recently.

Spurred on by the conference presentation and the fact more and more flights are carrying LoRa I invested in one of the Raspberry Pi expansion boards sold by Uputronics and built up another prototype tracker with a working LoRa module.

I have done talks at various radio clubs and societies and demonstrated it working but hadn’t actually received a ‘real flight’ as opportunities have been scarce due to the weather. However in the few weeks I have tracked a couple of flights receiving both telemetry and image data, getting a couple of complete images from the imaginatively named ‘SPACE’ flight.

Dave Akerman also flew a flight experimenting with multiple payloads using Time-division multiplexing (TDM). It had 10 small of “AVRLoRaNut” trackers (of Anthony M0UPU’s design) all set to the same frequency (434.450MHz) and same transmission mode. The trackers took turns to transmit, with each one allocated a particular transmission slot in a 20-second cycle. The cycle was GPS-timed but, if any tracker lost GPS lock then it derived timing from the transmissions from the other trackers (the LoRa devices are also receivers) All 10 trackers were suspended from the same balloon. This was in preparation for the ‘Operation Outward‘ re-enactment next year (Steve Randall gave a presentation on it in the above conference video starts 1 hour 16 mins in)

I successfully received telemetry despite the flight not being local and constantly heading away from me as can be seen in the screen shots.

Always a busy man Dave also flew a flight with an experimental camera setup. The SSDV images this time came from a Nikon compact camera, connected to the Raspberry Pi via USB, and using gphoto2 software to take and transfer images to the Pi where they were stored, resized and converted to SSDV format for transmission. These were large images with a high quality SSDV setting so lots of packets per image, approx 1400 per image in testing. 

This flight was using a 868MHz LoRa device, rather than the usual 434MHz due to the IR2030 restriction on bandwidth and duty cycle. Dave was using his Turbo-X or Mode 4 setting which is as fast as LoRa will go within IR2030 bandwidth restrictions (approx 8 packets / 2k bytes per second)

I hastily ordered a 868MHz device and soldered it in the spare slot on my gateway and built a collinear for 868MHz similar to the one I built for ADB-S reception (see video here).

You can see it lashed up just below the dual-band collinear – not ideal mounting and it wasn’t tested in anyway, built blind!  The less than optimal setup at UHF, the insane data rate and the distance (>100miles) were going to make reception difficult, so I was pleased I did manage to receive telemetry and image packets.

Most of the current LoRa development in the HAB community has tended to be on the Raspberry Pi due to the use with SSDV and the easy availability of cameras and ready built kit. LoRa is of course available on the Arduino platform and I had purchased a couple of ‘Dragino’ shields (pictured below) with a LoRa device on.

Dave has done some work on a AVR tracker software and a simple Arduino ‘Serial’ LoRa receiver. The receiver connects to a host PC appearing as a serial port and by running some gateway software the receiver can be configured via the serial link and received data is sent back to the gateway to be uploaded to the Habitat tracking system and SSDV system – the software can be seen here during the ‘Operation Outward’ test flight.

This gateway software is written in Pascal using Delphi and is not as functional as the Raspberry Pi Gateway software. Dave has made the source code available but I am not au fait at all with Delphi however I installed the free development IDE and intended to get in and make modifications but it seems to require a non-free(?) library for the serial comms so ditched the idea.

Instead I have spent the last few days developing a C# .NET version using Microsoft Visual Studio (the community version is free) and also have been modifying the Arduino code in the receiver to add functionality, such as storing the SSDV images locally.

It is still a work in progress but I have made a video showing the current state

Anyway as Cilla Black would say it’s been a Lorra Lorra Laughs!

Latest antics

Here I am a month after the last post and it is has been a month of very little ‘radio antics’.

I was acutely aware that since the end of September my wife had become a radio widow so promised not to lock myself away in the shack for a while and have been doing some much needed painting and decorating around the house.

I haven’t been in much of a radio mood anyway as I have been unwell and am still not fully over my last wobble. Band and weather conditions have been rubbish with a sustained period of high wind and rain including storms Abigail and Barney. As a precaution I dropped the pole and it became apparent I had some maintenance to do on the OCFD.

The shack too had been in need of some sorting out, which I thankfully I did muster enthusiasm to tidy up.

While being largely uninspired I haven’t been completely radio silent, I did get on air for the South Kesteven ARS 2m net but found myself suffering some QRM again

It isn’t the first time I’ve seen this sort of signal, but I had thought it had gone away, it seems it is back and stronger! This was an ARISS contact I monitored back in 2013 before I was licensed with a similar noise.

After using the SDR to identify the noise I realised I have been neglecting the FUNCube Dongle for far too long. So ordered some new SMA adapters from HamGoodies and pressed it back into service. I have been using it to decode the telemetry from the FOX-1A (AO-85) satellite with the updated software and have now got myself on the leader board even if the collinear is currently horizontal about four feet off the ground!

South Kesteven ARS had a talk in October by Sean Burton 2E0ENN about amateur DMR where he demonstrated some handsets and the new DV4Mini which allows gateway and internet linking.

I remembered I dabbled a few years ago with decoding PMR DMR using the SDR and a scanner with a discriminator tap using various programs but they were very hit and miss at the time. I reacquainted myself with the various projects and had a go at decoding some amateur transmissions.

I downloaded the latest program called DSDPlus  (support at RadioReference.com) and monitoring the nearby GB7RR DMRPlus repeater managing to get some clear decodes with little effort.

Finally this week I gave a presentation at SKARS on the subject of HABs and how to plan a HAB launch. Following on from the Eggsplorer-1 and Hamfest “Pigs In Space” HAB launch I decided to try to explain everything I had learned for anyone else contemplating giving it a go!

It was a long talk (perhaps too long) as I covered everything from building the electronics, software, making the payload box, getting the right balloon, parachute, gas, obtaining permission and then the prediction, launching tracking and recovery.

It was a great turnout with a lot of interest.

Hamfest Balloon – Some analysis

It has been five days since PINKY and PIGLET had their successful flight into the stratosphere. I have been studying the telemetry data and the photographs. I am really pleased with them but it makes the failure of previous Eggsplorer-1 mission to get any wow images more painful.

I contacted some local and national newspapers about the flight but with little response. The Register IT news website did put an article on http://www.theregister.co.uk/2015/09/28/pigs_in_spaaaace

I checked out the telemetry statistics on http://habitat.habhub.org/stats/ and was impressed with the number of people who tracked (as can be seen in the pie chart below) I know that several interested parties have since visited the UKHAS wiki and have been asking questions on the IRC channel on how to do a flight and/or develop their own trackers. Naturally I have also been thinking about some possible future flights.

While the novelty of flying something into space, be it a toy pig or an egg is satisfying I would like to make any future flight serve some purpose, whether collecting more data or ideally doing some experiment with radio even if it within the constraints of the UK draconian regulations when operating in the air!

One set of data I did extract was the temperature profile during the flight. PINKY had two sensors, one internal to the Styrofoam box, the other external. PIGLET also had a temperature/pressure sensor but it was giving odd readings during the flight so have ignored that.

The graph shows internal/external temperature recorded by PINKY against altitude, there are two plots for each showing the ascent profile and the decent. The lowest temperature recorded by the external temperature was -49.5°C   (-57.1°F) and the foam did a good job of insulating the internal electronics, though it drop below 0°C during the decent.

One thing I will do on the next flight (if it happens) is take a lot more photographs, using a 32GB memory card I could have held a lot more images. Also I will look at embedding the GPS coordinates (geotagging) into the image files.

I will also put on board a video camera, I did purchase a cheap dash cam type for £20 one off eBay for the Eggsplorer-1 but didn’t use it because of sea-landing, I need to sort out powering it as the internal battery wouldn’t last for the duration of the flight.

I have still to investigate the issues with the LoRa as to why it failed. This weekend Dave Akerman is flying three balloons in succession with LoRa tracker modules. They will be set up to work in a mesh, receiving and repeat each others telemetry. Sounds an interesting experiment, I will have to set my LoRa gateway back up and attempt to receive them.

Hamfest HAB Flight – Mission Debrief

The National Hamfest high altitude balloon flew on Saturday and Pinky Pig reached a maximum altitude of nearly 26km (25,927m / 96,873 feet) as pictured above.

The flight originally planned for Friday had to be postponed due to wind direction and restrictions but I had sort approval for both days and was able to fly on Saturday. The conditions were perfect on launch day, clear blue sky with little cloud and almost no wind.  Flight prediction put it landing around 25km away.

Both payload trackers worked flawlessly, PINKY the high speed RTTY successfully sent SSDV as well as telemetry and the backup tracker PIGLET sent the slow speed RTTY telemetry. Trackers from all over the UK as well as France, Holland and Poland received data and uploaded data to the UKHAS website.

The received SSDV images can be seen at http://ssdv.habhub.org/PINKY

The flight path can be seen below

The flight can be seen visualised in Google Earth below and while the 26km altitude was impressive it was around 4km less than I’d planned.

The launch certainly created a great deal of interest at the Hamfest, on the Friday we setup the club tent for South Kesteven ARS with a tracking station and demonstrated the payloads to interested visitors. Stewart (M0SDM) used his Land Rover with a push up mast for a pair of collinear X-50s so we could receive and decode.  The mast and the Land Rover generated just as much interest.


On the Saturday I was assisted by my brother David (M6GTD) and just before noon began filling the balloon watched by a large crowd, as can be seen on Dave’s (M0TAZ) blog http://m0taz.co.uk/2015/09/national-hamfest-2015/
Picture by Dave M0TAZ
Once filled to give the correct lift I sealed it off and checked everything was working then without a breath of wind slowly let the balloon rise, taking the weight of the payloads and once I was sure there were no aircraft flying nearby I let her go. The sky was clear and the balloon went up near vertically and could be seen for quite a long time as it ascended. Representatives of the RSGB and RadCom were in attendance to take photos and did a quick interview. 
The tracking station was then full of people as the telemetry and pictures started to be received. It was great to see the huge interest in the balloon. 
As the balloon started to near the planned maximum altitude I began to get ready to set off to recover it then suddenly I was told it had burst sooner than expected. I got a hurry up at which point the laptop and mobile connection decided to stop working! However I knew where to head off with my poor brother trying to sort it out as I drove.
Stewart telephoned and gave me directions of where the live prediction and tracking had put the landing spot. My wife also set off from home to come and assist. In the car we were receiving a signal but were struggling to decode and couldn’t get on the internet to check the tracking. 
I eventually pulled up near the landing zone, while trying to decode the weak signal another car pulled up with two radio amateurs who had been tracking the balloon. I was a little preoccupied and they eventually said they were off and wished us luck. I then realised we were the wrong side of the hill and turned around and drove up to the top and the signal strength increased.
Stewart had phoned to tell me to find the Viking way footpath, as we reached ground zero we saw the other amateurs car and they were setting off down the footpath! It was my flight I wanted to be the first to find it!
My wife then pulled up and was about to set off after them! Then I started getting successful decodes! With the new landing position in the GPS my wife raced off in hot pursuit as I sorted out the car and then followed her with my brother. It was a reasonable walk of around 800m and as we got near it became apparent the other team had been using the online tracker and had only got the last received position which had been sent from around 254m altitude. However the payload was still transmitting strongly and we were decoding it and it was reporting it was in fact at 115m altitude – they were therefore several hundred meters in the wrong direction.
Our accurate location gave us the edge and a quick hop up a bank into a stubble field and a 200m jog my brother spotted the parachute… we had found Pinky and Piglet and got there first!
 I was surprised to find most of the balloon still attached, it hadn’t so much burst as split in a single tear
The payloads had no damage, other than the antenna being bent by the landing
PIGLET had landed as planned and tested, I had put the battery pack at the top of the box the top heavy center of gravity causing it to roll on landing so the antenna would be upright. It was in a perfect orientation hence the strong signal.
The other chase team turned up and congratulated us then left…  my apologies but I was in my own little happy place to be sociable. We then then had the obligatory team photograph before setting back to the Hamfest.
It has been an excellent experience and adventure.  The pictures are better than I could have hoped for! Thanks to my understanding wife, my brother David and Stewart for setting up the antennas for the tracking station and manning it on his own while we went off to recover the payload.
Thanks to the organisers of the National Hamfest and Graham Boor (G8NWC) for asking me to do the flight and helping fund the venture and I hope it succeeded in publicising the event and the hobby.
I have now downloaded all the photographs from the onboard camera and they can been in my Flickr album at https://www.flickr.com/photos/nerdsville/sets/72157658732989849
Updated – I realised I didn’t put the actual landing position on this post, so here it is

Hamfest HAB Launch likely to be postponed to Saturday

Given the latest flight path prediction, weather forecast and approval restrictions I will unfortunately have to likely postpone the National Hamfest high altitude balloon till Saturday.

The forecast for tomorrow is strong gusty winds at ground level which isn’t ideal for launching, but that is the least of the issues.

The current flight predictions for tomorrow are not good. The prediction model used is accurate and for the size of balloon I have and the amount of helium at my disposal even a maximum fill giving the maximum ascent rate and assuming the calculated decent rate for the parachute it is still putting the likely landing right on the coast. Earlier in the week the landing wasn’t quite as marginal but as the model’s data set have been updated it has drifted further eastward, it is odds on it will actually land out to sea.

However the real show stopper was when I received the CAA approval for the launch this morning. They have put a restriction not permitting a launch if the balloon and payload is likely to go on a North Easterly or Easterly path that could interfere with operations on local military airfields.

This is the predicted flight path, generated by the CUSG Landing predictor at predict.habhub.org and the flight path currently goes directly over RAF Cranwell but not at a high enough altitude. 

Flight prediction for Friday

Saturday is forecast to be a much calmer day with a predicted path as shown below

Flight prediction for Saturday

There would be no issues with the airfields for that flight path and has the advantage of going almost straight up and landing close by.

Apologies to those wanting to track on Friday, but the situation is out of my control and I would be foolhardy to ignore the prediction and  it is very unlikely it will change significantly to allow a flight tomorrow so I hope you can all track on Saturday. I will still be at the Hamfest tomorrow with the equipment if you want to know more about what it is all about.

Hamfest HAB – Pre Launch Update

Not long now! Just three days left till the National Hamfest and hopefully the launch of my second high altitude balloon.

Balloon, parachute and helium have all been purchased and payloads have under gone final testing and have been put to one side ready for the flight which should hopefully be around 12pm on Friday 25th September.

The SSDV payload callsign PINKY will transmit on 434.575MHz USB RTTY 300 baud 880Hz shift ASCII-8 no parity 2 stop bits.

SSDV Test image

the backup telemetry tracker callsign PIGLET will transmit 434.150MHz USB RTTY 50 baud 380Hz shift ASCII-7 no parity 2 stop bits

They will transmit using the UKHAS telemetry protocol and can be tracked on tracker.habhub.org for information on how to receive and upload data to the tracking system visit the UKHAS wiki some information and useful links have been collated on the AMSAT-UK website

I was hoping to also transmit using the LoRa system, using the callsign PERKY. The transmitter had been successfully tested but a last minute gremlin has struck and it stopped working this weekend, I have been unable to locate the fault and suspect it is the actual module and with time being short have all but given up getting it working. If I do get it working it will be on 434.450MHz in Mode 1

PERKY seen working on SDR

PINKY & PERKY tracker

I have already detailed the PIGLET payload in an earlier post. The PINKY/PERKY payload is constructed on strip board and was originally meant to to be a prototype, hence the rubbish layout. I had planned to build a better laid out version but the tight time scale, stresses and demands of work, commitments with the radio club not to mention nursing the wife as she recovers from a major operation scuppered that plan. Being pragmatic I decided it didn’t need to be work of art to work! I have secured all the connections with hot glue and it has been drop tested several times.

“Pinky” pig will be the passenger on the day, donning his fetching headset. Getting him in the right position for the camera was tricky.

I am still waiting for the CAA approval, should hopefully get it soon. I have put in a request for both days of the Hamfest just in case, the latest prediction at predict.habhub.org shows if I get the fill right I might just escape a watery landing on Friday, however Saturday looks more promising at the moment – also the forecast for Friday at the moment also has strong gusty surface winds, which could make the launch problematic. I am still planning for Friday since conditions and predictions do change.

Friday prediction as of 22/09/2015

Saturday prediction as of 22/09/2015

I and other members of South Kesteven ARS will be in attendance with a tracker station on the day, so please introduce yourself and perhaps join the club?

Please don’t mention anything to do with other pigs in the news..

Hamfest HAB – “Pigs In Space” Preparations

Already a week into September and not long now till the National Hamfest where I and the South Kesteven ARS are launching a high altitude balloon launch subject to CAA approval. The documents have been submitted so just waiting for the nod.

The balloon and parachute have been purchased from Steve Randall (G8KHW) at Random Engineering, using the same size as I did for the Eggsplorer-1

I had joked about sending some “Ham into space” on this flight but following the smelly end to Eggsplorer-1 have opted to play it safe and avoid food! Instead will be sending up a toy pig (well a small squeaky dog toy)

Similar to the Eggsplorer-1 the main tracker will be a Raspberry Pi fitted with a camera and two transmitters.

The tracker is based on the “Pi In The Sky” code base/design by Dave Akerman (M0RPI) and Anthony Stirk (M0UPU) with some modifications since I am building on simple strip board using a different GPS module/interface and omitting any power supply monitoring.

On the Eggsplorer I used an old Pi Model B but was forced to butcher it to reduce the power demand by desoldering the network/usb chip. This time I am using a Model A+ which is smaller/lighter and has a much reduced power demand and with the locking micro-SD card socket will hopefully prevent a repeat of Eggsplorer-1’s failure mode.

PINKY & PERKY are progressing well, just waiting delivery of some strip board and they should be completed in the next day or so.

PINKY will be 300-Baud RTTY, sending telemetry along with SSDV image packets using the UKHAS format.

PERKY will be using one of the LoRa modules again sending telemetry and SSDV but with greater resolution and speed, but will require a LoRa receiver/gateway (see Dave Akerman’s website).

While the SSDV is attractive to tracker enthusiasts the high speed RTTY is more difficult to receive, so I will be flying a secondary ‘backup’ tracker. The use of a backup proved invaluable on the Eggsplorer when the main tracker failed.

PIGLET will be a 50-baud RTTY transmission with telemetry and should prove easier to receive.

I finished PIGLET at the weekend

Again built on strip board it is based around the ATMEL ATMega128 micro-controller using the Arduino system with a number of off the shelf modules connected to it.

It has one of the GY-GPS6MV2 GPS modules I blogged about last year feeding into the UART. The NTX-2B transmitter (frequency agile version from Hab Supplies) and a I2C BMP180 pressure/sensor module (not visible as mounted to measure external conditions) It also has a small boost converter to supply 5V and extract all the available power it can from the 3-AA lithium battery pack.

One change compared to the EGG1 tracker is to use a PWM output from the Arduino to generate the RTTY tones rather than a register voltage divider (guide here) which seems to give a cleaner signal.

The antenna is simply copper wire making a 1/4 wave ground plane. The ‘box’ are some layers of styrofoam glued together with UHU-Por with duct tape, some straws and beads for safety. Just needs the batteries fitting and the lid fixing with more duct tape and PIGLET is ready to fly.

Full details of frequencies will be posted nearer the time.

MADHEN Eggsplorer-1 – We’ve got the data!

Following the euphoria of the Eggsplorer-1 payload being found six weeks after launch washed up and retrieved from the beach in Terschelling, Netherlands it has been an agonising wait to see what the Dutch police would send back. My impatience got the better of me last week and I contacted them directly to be told that unfortunately due to the awful smell and condition of the box they had simply removed the memory card and had posted that back as requested.

More days past and I was beginning to think irony was going to play a cruel trick and the card after its fantastical journey would end up lost in the post. I shouldn’t have been so pessimistic as it arrived today! Along with the card was a detailed map showing the final location and labels from the side of the box.

There was a nice note from the police.

The SD memory card seemed to have had survived more or less intact, though there was some corrosion on the contacts and crucially a small corner of the card was broken off.

The plan was to use the Win32 Disk Imager program to make a direct raw image of the card and work on that copy. I first used a small wad of wire wool to gently clean up the contacts

I was encouraged when I inserted the card into my Microsoft Windows laptop and it was detected, however my heart sank when any attempt to access it or use the imager program was met with an error. I gave it another gentle going over with the wire wool and thankfully was then able to make a image file, the next stage was to extract the precious data.

The card of course contained the Linux based Raspberry Pi file system and in order to access it on a Windows machine I used the freeware linux-reader from DiskInternals which allows access to Ext2/Ext3/Ext4, HFS and ReiserFS file systems within Windows.

It was a simple case of using the “mount image file” option and the partitions were then accessible and everything appeared intact, there were images on the card unfortunately not the “egg in space” image I wanted, just some nice “egg in the clouds” shots.

The telemetry log file confirmed the worst, the flight computer had indeed stopped/crashed at approx 2.5km up and no further images had been captured of the 31km accent into the stratosphere (confirmed by the backup tracker) I had hoped the transmission had stopped because of a fault in the antenna or the radio module board alas this wasn’t the case.

On the day of the launch I did have problems with the payload not booting up. It had worked flawlessly under test the previous weeks and I had secured everything in the box ready for the flight. The day before the launch I had spotted there was another balloon going up in the UK at the same time and we had both opted for the same frequency. So at the eleventh hour I was forced to take out the SD card to change the configuration to prevent the transmission clash.

The launch day start up problem was the SD card. I had removed and reinserted it to get it to start up and secured it down with plenty of gaffa tape. Looking at the card now and the fact the broken corner is old damage I am convinced this is the reason for the failure as the card may well have become dislodged due to turbulence.

While slightly disappointed it is still a miracle I have any images at all and can only thank Jan and the Dutch Police again.

I have certainly learned a lot and hope the National Hamfest HAB that I and South Kesteven ARS are flying is more successful

MADHEN Eggsplorer-1 FOUND!

The payload for the MADHEN Eggsplorer-1 High Altitude Balloon that I and the SKARS team launched in June has been located washed up on a beach in the Netherlands. Amazingly the egg was still intact inside the capsule.

On Friday evening I went to the Hucknall Rolls Royce ARC to give a presentation of HAB flights including details of the Eggsplorer-1 launch and its subsequent apparent loss at sea, then yesterday we had a trip to North Yorkshire and visited the Boon Hill Show and I admired the display of eggs within the produce tent.

It must have been synchronicity since a few hours later despite the poor mobile phone coverage I spotted a message on my mobile phone. It was from Jan Wouter Kramer from the Netherlands, whilst out on a remote beach in Terschelling he had found the Eggsplorer-1 washed up and taken some photographs!

Nearly six weeks to the day after launch she had been found with the egg apparently intact! I tried several times to ring back but the poor mobile coverage prevented it so sent a text message hoping it would reach him. I couldn’t wait to get home to and finally did just before midnight.

I frantically logged on to check emails

Hey Andrew

Found your email on the site.
These are the pics we made.

We found it today about 14:00 during a walk on the beach of Terschelling in an area were not many people are walking because it’s more than a two hours walk from the nearest houses.

As you can see the egg wasn’t damaged but had probably lost it’s strength. While trying to investigate what was inside the ‘bulb’ it broke open and the egg broke in two parts. It was nearly empty. Only a few cc of dark ‘water’ was left in it with a terrible smell …….

Best Regards !

Jan Wouter Kramer

The pictures were amazing

I emailed Jan back as far too late in the night to telephone

Hi Jan, 
Sorry I was able to take your call this afternoon but was out of coverage for most of the day.

Thank you very much for the information and pictures of the Eggsplorer-1. It was our first ever balloon flight and after it landed in the sea I thought we would never see it again.

Amazingly it appears very much intact, shame about the egg being rancid, would really have liked to get it back and would have paid for shipping – but I can imagine the smell was awful.

The Raspberry PI circuit board inside the box had a SD memory card which was held down with gaffa tape, I am not sure if it is still attached and it may have contained some photos of the flight taken with the onboard camera. However given the remoteness of the payload I understand if it is too far to return for such a slim chance.


Andrew Garratt (M0NRD)

As I wrote given the remoteness and the rancid condition of the egg I couldn’t really expect Jan to go out again to collect it but had a fantastic text message this morning

Hi Andrew, thanks for your email. The good news is that I found the local police willing to pick up the remains of the eggsplorer. (They are allowed to drive on the beach by 4×4) I just got a phonecall that they found it and are willing to send it back to you.
So you have an address for me ??
Best regards
Jan Wouter

As you can imagine I am totally EGGSTATIC!!

I rang Jan this morning and had a great conversation, seems he visits here every year and goes beach-combing with his son, they have never found anything quite as exciting as this!

So MADHEN Eggsplorer-1 has traveled 31km into the stratosphere, landed in the sea and traveled approximately 370km from launch site to its final resting place on the beach. The World Egg Throwing Championship people are very eggcited.

Just hoping that there are some photos on the card if it has survived, cannot be sure from Jan’s photographs. Since the flight I have suspected two possible fault scenarios, bad connector on the SD card on the Raspberry Pi or the antenna was broken off due to the backup tracker suspended underneath. I am hoping it was the latter and the card is recoverable and readable since it would contain pictures.

The backup tracker is also there but has lost its polystyrene egg cover, gps-antenna and battery pack but can see it is still attached to the main payload. The question is how long it has been on the beach? Given the relatively good condition of the box and the labels are still attached it may have been quite soon after splash down.

I am indebted to Jan for taking the trouble of contacting me and the police, I can’t thank him enough! When I get the payload back I will post an update.

All the members of SKARS are eggcited and gives new impetus for the National Hamfest flight next month.

Sneeking off to track a HAB

Following our sojourn to Scotland we spent this weekend visiting and catching up with the relatives, as a result radio activity was a little limited.

Yesterday we were visiting my mother-in-law and I had seen that the University of Southampton Spaceflight Society were launching a High Altitude Balloon from the New Forest. I am never one to miss the chance to track them and decided at the last minute to throw the Alinco DJ-X10 receiver and an audio lead into the bag with the laptop which by happy coincidence we were taking since it contained the holiday photographs.

After an enjoyable Sunday lunch I dutifully did the washing up and then as the others succumbed to postprandial somnolence I sneaked off to see if I could receive anything as the flight was already well under way.

I put the Alinco on an upstairs windowsill with the W-881 Watson Super Gainer antenna fitted. The radio which has SSB capability was still tuned to 434.650MHz as this was the frequency I used on the EGG1 tracker and amazingly I heard clear RTTY telemetry of the CHRISHAB tracker and connecting it to the laptop with a simple earphone-to-microphone input lead was getting clear decodes.

Being a silver surfer my mother-in-law has a broadband connection so was able to upload the packets to the tracker system.

I left it running while I returned to be sociable. When I checked back later the flight had ended but I was more than happy with the number of decodes I had achieved with this modest set up and proves with all things radio it pays sometimes just to give it a try!

The previous day I visited my mother and got to try my brother’s very nice new Yaesu VX-8R hand held. I made a short QSO with MX0PPC the Central Amateur Radio Circle (CARC) who were running some intermediate classes that afternoon. My brother is getting to grips with it and its in built APRS and GPS and soon hopes to be spotted by the International Space Station digipeater.