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

National Hamfest Balloon Launch

Following my maiden high altitude balloon launch last month of MADHEN Eggsplorer-1 at the World Egg Throwing Championships I have agreed to attempt another launch at this years National Hamfest which takes place on the 25th-26th of September at the Newark Showground.

Once again I will be assisted by the members of South Kesteven ARS and hopefully this time it won’t end up splashing down and being lost at sea.

I intend to have a SSDV system running on a Raspberry Pi using the usual UKHAS RTTY protocol and possibly this time a LoRA transmitter which allows faster transmission and higher resolution, however this requires ground stations to use a LoRA receiver, this are straightforward to build. I have done some experiments with the code base developed by Dave Akerman but didn’t implement them in the Eggsplorer-1

As to any special payload? Well following the yokes about “Ham n Eggs” following the sending of an egg in the stratosphere, who knows….?

Anyone interested in joining South Kesteven ARS and being involved then contact me via the club website at www.skars.co.uk or our facebook page

STRATODEAN – High Altitude Balloon

After yesterdays successful first attempt at receiving the telemetry from HABs (High Altitude Balloons) I spotted another was being launched this morning, the STRATODEAN Project.

The STRATODEAN team is made up of Mark Ireland and Cassie Phelps, two graduates from the Forest of Dean in Gloucestershire who were launching their payload from their hometown.

The launch took place just after 10am, and I set the receiver going and was getting some faint signals but no successful decodes and took the dogs out for a morning walk, a few hours later I returned to find the signal had increased in strength and decodes were occuring.

I carried on receiving successful decodes after the balloon burst and it was making the decent, the final decode being received as it was around 700m from the ground, quite near the final landing spot.

I managed to get the spacenear.us tracker working (by turning off adblock plus) so was able to follow the track of the payload in real time as decodes were received.

Congratulations to the Stratodean project it was an enjoyable few hours.

99 Red Balloons, well actually 3 High Altitude Balloons on 434MHz

In my news feed this morning was an innocuous article from the Southgate Amateur Radio News website (which is a must have subscription for anyone interested in amateur radio)

It simply said “Several 434 MHz balloons launch today” but it was enough to pique my interest, the first launch this morning was the NSE/CHEAPO balloon set to launch at 9am from Bicknacre, Chelmsford, Essex, UK.

I was vaguely aware of these balloons and the High Altitude enthusiasts but I had never received or made any attempt at receiving them, but shortly after nine I started up the FUNCube Dongle and tuned to 434.650MHz with the discone in the loft and got a pretty decent signal, which I recognised as being RTTY.

A quick visit to the UKHAS UK High Altitude Society website and I had downloaded the dl-fldigi application which decodes the signal from and uploads the data to a central website.

I didn’t have any luck getting a decode from NSE but I was prepared for another attempt, so when I returned home this afternoon I managed to received the AURA balloon which launched from Great Malvern. I received quite a few success data packets which got uploaded.

I also received the last balloon this afternoon launched by the Queen Mary University from the Elsworth Site near Cambridge, around 4pm, but the signal was a little too scratchy for a successful decode.

I have since discovered that the transmitters in these balloons are only 10mW, but because of the line of sight they can manage several hundred miles, but even so the setup I was using wasn’t the most efficient for reception.

A similar balloon being launched