Project Horus FM Rptr Balloon Flight on Sun 15th April 2012

[VK5GR]

Everyone,

I wish to advise that the Project Horus high altitude balloon group based in Adelaide is currently planning for a balloon launch on Sunday April 15th, shortly after the WIA Broadcast (planning to be in the air around 10-11am ACST). This launch will be an amateur radio oriented launch, with three payloads of interest to amateurs, intended to coincide with the WIA field days. The launch designation is Horus 23.

1. The group is planning on flying the FM voice repeater again. New frequencies will be used compared to last time (which we are still finalising) and will be updated here as soon as known. The repeater will operate with a 70cm uplink and a 2m downlink. From previous flights, it should be possible to access the repeater from up to 800km away at apogee with about 30-50W (a beam will help overcome the inevitable FM capture effect problems too). The downlink is easily audible on any reasonable omni, although if you are under the balloon's flight path you may see over 20dB fades (the tracking and recovery teams use cross dipoles on the roofs of the cars to help at least one way with the link budget). The Amateur Radio Experimenter's Group will be running net control on the voice repeater as VK5ARG from launch control in the Adelaide Hills.

The repeater frequencies will be:

Uplink: 438.900 MHz FM with a CTCSS Tone of 123Hz
Downlink: 144.650 MHz FM (in the 2m experimental segment)

The output also has a CTCSS tone being transmitted at 123Hz (optional)

2. APRS will fly on this flight on 145.175. VK5ARG-11 is the expected callsign. We will be also able to look at the new http://aprs.fi/ horizon ring prediction service on this flight. Telemetry format packets are also broadcast now on APRS.

3. The ever reliable primary 300baud RTTY telemetry beacon will also fly - at this stage it will be on 434.075 (note update) (+/- 5kHz thermal drift). This signal is used as part of the group's "distributed listener" telemetry network where any amateur receiving the data can upload what they are hearing over the internet. The data, which is sent to the http://spacenear.us/tracker website contributes to the landing zone predictions used by the chase teams. The chase-tracker teams have 3G Internet in their vehicles and are actively looking at that data, so it is one way amateurs can have a behind the scenes involvement in the flight's success. NOTE: this beacon only runs 25mW, however we have had people from the horizon and at times beyond still be able to decode and contribute, so why not give it a go! If you would like more information about the software setup required to participate in telemetry recovery take a look at our tracking page: http://projecthorus.org/?page_id=336

Confirmation that the flight is a go can only be given ultimately on the morning of the 15th. We are subject very much to the weather and have various constraints on where we can fly, so the potential for the mission to be scrubbed exists up until the last minute. We will endeavour to update the forum once we get closer, and will post notices on the DX Cluster once it is in the air. Flight time should be around 2 & 3/4 Hrs.

If you would like to find out more about the project please visit our website http://www.projecthorus.org/ or Vimeo channel http://www.vimeo.com/channels/projecthorus/ for some short films of our past activities. More information is expected to be posted about the forthcoming flight to the group's blog on our website during the week.

Regards,
Grant VK5GR
for Project Horus and the Amateur Radio Experimenter's Group

Updated: Tuesday April 10th with final repeater frequencies

[VK2KRR]

thumbs-up-ok.gif (5.03 KiB) Viewed 3148 times

[VK2XSO]

I'll jump in on this one too. Next weekend will be an "UP" weekend.
Not to detract from the Horus guys who have given the Helios guys some help.

The Tamworth Radio Club is counting down for a launch of LOKI 1 and HELIOS 1 on the 14th April 2012.
LOKI 1 can be tracked using APRS callsign of VK2BTW-11 and HELIOS 1 can be tracked using APRS callsign of VK2BTW-12.
LOKI1 will be using Hydrogen as the lifting gas and HELIOS1 will be using Helium.
HELIOS is the efforts two young club members Liam McBride-Kelly and Ricardo McMillian.
The payload consits of a go-pro camera and both SPOT and APRS trackers.

LOKI has a more complex payload. It too has a video camera and an APRS tracker but will also carry an ATV transmitter and a geiger counter.
The ATV picture downlink frequency is 1250MHz FM Vertically polarised no audio subcarrier. The transmit power is 1.5 Watts.

The geiger counter is a simple gamma/beta tube to monitor cosmic radiation.
Previous measurments using this kind of GM tube have given readings of 3 millirads per hour at 40,000ft.
Normal background radiation for East Coast Australia at ground level is typically 0.05 millrads.
The downlink frequency is 433.920MHz and modulation is CW. Output power is 100mW
Some frequency drift is expected with temperature.

A constant unmodulated carrier is heard with "ticks" from the geiger counter.
Each tick is one partical of radiation. At altitude it is excepted to hear over 300 clicks per second or 300Bq

These are our first attempts at balloons, so we're expecting them to be a horrible failure but a lot of fun

No specific time is scheduled for launch but it is expected to be about 9am EST on the 14th April.

[VK5GR]

Sounds like you have some fun planned Ash! The geiger counter sounds interesting. Going to be very interested to hear how your ATV goes too. We have looked at 23cm FM TV but worked out the link budget was marginal to see it at apogee. Currently rethinking and may try a 444.25 AM ATV transmitter on a future flight at about 3W (contacts from the USA tell us that should give us about 300 miles range at 3W on 70cm).

Let us know how you get on!

Regards,
Grant VK5GR

[VK5GR]

Ash, one flight that could be fun to try one day is a sync'ed launch with dual repeaters. With both Horus and Helios flying interlinked repeaters contacts from VK4 to VK5 should be possible at apogee (and everywhere in between).

Something for the future

[VK2XSO]

We're not expecting too much from the ATV transmitter, but with some high gain antennas and low noise pre-amps we're hoping to learn the hard way how practical it is. I did have some other ideas for improving the performance like a downward facing helical antenna but I decided to keep it simple first.
If the video drops out at even 30,000ft, then we will still have some interesting and useful information.

The geiger counter is small and draws almost no current compared to everything else. I would have liked to have given it a bigger transmitter. The suggestion was to put it on the video sound. It's something to think about for the future.

A dual launch with dual flying cross band repeaters is very interesting. I know I've heard a couple of people suggest it before and I think it would be bucketloads of fun.

I have a design ideas for a couple of other balloons too. Some of them are a little whacky and need some time to polish off the rough edges.

Getting a payload into a neutrally buoyant flight is the one we continue to entertain.
Using several smaller balloons to lift the payload. As balloons rise and pop they reduce the lifting capacity till it no longer rises and there is still enough buoyancy to hold the balloon at height for an extended period of time.
The other variation on this is to use an over weighted balloon for the decent. Two balloons for the lift, one pops and now the balloon is negative buoyant and descends slowly. Much slower than if it were on a parachute.

And there is no shortage of payloads to try out. The geiger counter was just one which I know will produce some interesting results.
I've been wondering about how much very fine copper wire I can lift.

Another thought was flying a small balloon into a thunderstorm. I can't even imagine what kinds of nasty things could happen to it, but just thinking about it is fun.

In any case I think we'll be having some more fun in the future.

[VK2AVR]

Very interesting guys, would be neat to work crossband through a balloon, alas being in VK2 not much chance. One day!!

Ash that geiger counter is a cool idea, that would be quite interesting to listen to. Was the motivation for 433.92MHz based on readily available consumer hardware? You will have car/garage remotes competing with your signal but the modulation you've chosen should cut through it. Directional antenna will also help.

Geoff

[VK5PJ]

Never day Never Geoff

Very interesting guys, would be neat to work crossband through a balloon, alas being in VK2 not much chance. One day!!
Ash that geiger counter is a cool idea, that would be quite interesting to listen to. Was the motivation for 433.92MHz based on readily available consumer hardware? You will have car/garage remotes competing with your signal but the modulation you've chosen should cut through it. Directional antenna will also help.
Geoff

One of the horus flights made it to the Pacific ocean not long ago, mind you I think it was a bit low by then

[VK2XSO]

Was the motivation for 433.92MHz based on readily available consumer hardware?

Actually, it was a box of about 100 transmitters I bought from the Jaycar stand at Wyong a couple of years ago.
While they don't have a lot of power, they do fly on balloons really well and from 20,000ft they kick a***.
So at 100,000ft I expect a little reduction in signal strength, but yes with a good directional antenna I'm expecting some good results.

You will have car/garage remotes competing with your signal but the modulation you've chosen should cut through it.

Out where we are launching the balloon there isn't a lot of interference. Tests flights I've done with them before have not had any issues.
It's easy to add an amplifer to them, but with 99.9% duty cycle, it can suck down the power. Inverting the logic and it's harder to hear the clicks.

I usually carry a geiger counter with me most places I go. I thought it would be interesting to take it on a few flights with me.
I surprised myself and several other passengers at 38,000ft. So naturally I just have to find out what the background cosmic radiation is like at 100,000ft.

The circuit itself is actually very simple. It's basically a geiger counter version of a crystal radio.
The circuit that is flying is very similar to this one, but scaled down to be even lighter.
http://home-and-garden.webshots.com/pho ... 1318ufVtyb

The tube needs about 350V to operate. So a recycled disposable camera flash charging circuit is stripped of key components and used to generate the 350V.
The tube strikes, just like a coherer of ye olde, but rather than a mechanical reset the tube has a quenching gas which resets it after each strike.
The signal is passed through an isolating capacitor to the transmitter. It's very easy to pull the TX ENable low to cause the CW to modulate with the typical >click<.

The circuit runs on a single AAA battery, but for reliable results 3V gives it more than enough herbs to keep the tube charged even at high count rates.
In the future I may just PIC chip the counter and have it send the average in Bq every 30 seconds or so.

A small trade off for an extra PIC chip of weight less the extra battery weight required.

It's all fun.

[VK5GR]

One of the horus flights made it to the Pacific ocean not long ago, mind you I think it was a bit low by then

Actually it was at it's highest just before burst. I think we made something like 38.7km on that flight somewhere over the great dividing range.

[VK2AVR]

Ash sounds like awesome fun Building a geiger counter (the "clicker" style possibly with an MCU giving a count) has been on my todo list for a while. A few of my friends and I bought military surplus geiger meters but they only measure high level radiation (levels that would kill you). They do look pretty awesome though.

I figured being out in the country as long as you went out of town to launch you'd be fine. I have done a bit of satellite chasing and plucked ARISSAT-1 out of the ether with a 3 element yagi on 2m - that bird was around 250mW from memory and some 400km up, using FM. Was getting S7 on a good pass. 100mW CW with a 4-5 element on 70cm should be a ripper. Keen to hear some recordings of the radiation at different heights

Peter, yes if a balloon did drift this way it would be cool, one day it will happen

[VK5ZD]

Grant

Re CASR 101.E, are these classed as 'light balloons' or 'medium balloons' as they don't seem to fit either category?
i.e. they will exceed the 2m diameter limit for a 'light balloon' but are below the minimum lift capacity for a 'medium balloon'?

73
Iain

[VK5GR]

Iain,

I'm not directly involved with the CASA approvals so cant comment there. A question to put directly to Terry VK5VZI who has handled all of the CASA negotiations.

Grant

[VK5ZD]

Well done to the Tamworth Radio Club on their balloon flights, though it looks like you might have a bit of a hike to recover the payloads.

73
Iain

[VK5QI]

Congrats on the launch!
Looks like Loki needed more heat-sinking though, I'm seeing average temps around 50 degrees, and spikes to 80 degrees!

- Mark VK5QI

[VK5ZT]

Hi all

Looks like pretty good "textbook" flights for the two balloons at Tamworth. Very interested to see how the various packages worked.

Especially interested in how well the TV transmissions worked out.

For balloon 'novices' you would have to say an ambitious exercise very well done!!!

Cheers

Tim VK5ZT

[VK3MEG]

do you have them plotted on a map?

[VK3PF]

Hi Steve,

At the moment, you can see the 2 balloon tracks & the chasers by looking at:
http://aprs.fi/#!mt=roadmap&z=11&call=a ... ange=21600

Not sure how long the data is available.

Peter VK3PF

[VK2XSO]

A few of my friends and I bought military surplus geiger meters but they only measure high level radiation (levels that would kill you).

If you bought the ones from Oatley electronics... you're notice that the meter's are radioactive. They have radium painted dials.

Looks like Loki needed more heat-sinking though, I'm seeing average temps around 50 degrees, and spikes to 80 degrees!

You'd have to ask Mark VK2JMA about the temperature, but I doubt the sensor is anywhere near the heatsinks and it is more likely that it is the APRS transmitter RF was probably getting into it.

Especially interested in how well the TV transmissions worked out.

The ATV transmitter actually worked out very well.
From the launch site I was able to get a good solid P5 colour picture as it passed through 25,000ft and was able to see the clouds below and mountains in the distance. The payload was very stable and it didn't spin or sway very much. The shape of the styrofoam payload chassis would have had a lot to do with it.

By the time it was at 30,000ft I could not get a picture out of it. I could see sync bars and make out a tearing picture. There just wasn't enough power as it flew away. It was only a 1.5W transmitter, but the results were very good for what we did get out of it.
If I had been at home with my usual ATV setup I think I could have got (and recorded) some very good pictures from it.

So while the link budget doesn't support the effort, just trying it out was a lot of fun.
The on board recording camera may have failed and not taken any pictures, so what we saw may be all their was.

The geiger counter worked really well. Above 80,000ft it was very hard to hear with the gear I had on the move. Again, I think if I have been at home and had my 70cm multimode I could have made some very good recordings and got some great, useful and interesting data from it.
I notice Dave VK2JDS said he could hear it and recorded it from his QTH near Orange. He noticed it drifting in frequency much the same as I did.

I'm wondering how many other people heard it. In any case I think the geiger counter will fly again and in the future it will be given a higher power transmitter and/or maybe patched into the APRS data.

The APRS data is stored on the server for years. If you search for VK2BTW-11 or VK2BTW-12 and then look at the menu's on the right, you can select today's date and look at the data any time in the future.

I'm trying to work out how to look at the historical data in Google Earth 3D. It's easy and very cool to see it live in 3D.
Looking at the raw packets, the furtherest distance was to VK4NRL in Dalby. About 480km.

The ground crews were really good with getting the balloons inflated and launched. They did an excellent job and I enjoyed sitting back and watching everybody else do the hard work for a change. I haven't checked the video yet. I'll put some of it up on youtube soon.

The tracks of both balloons were strangely very similar and in some places they flew the exact same path over the ground. I'll be looking at the 3D data soon too.
The Helium balloon landed about 100ft up in a tree. One of the recovery teams has gone to get the chainsaw.
The Hydrogen balloon landed in a valley not far off a track. Brenda VK2FSMI spotted it first. She's an aggressive fox hunter, and be damned if she was going to let anybody else get to it first


In any case I think the club is now addicted to balloon flights. I've mentioned some new experiments for our next balloon. Other club members have agreed that the new ideas are even cooler than a flying gieger counter !

[VK5ZD]

Hi

Looks like Loki needed more heat-sinking though, I'm seeing average temps around 50 degrees, and spikes to 80 degrees!

You'd have to ask Mark VK2JMA about the temperature, but I doubt the sensor is anywhere near the heatsinks and it is more likely that it is the APRS transmitter RF was probably getting into it.

Higher temperatures are to be expected. Heatsinks rely on the air to remove the heat by convection. As the balloon gets higher there's less air to remove the heat so the temperature goes up.

73
Iain