Weather Balloon - Summer 2011

Manager: Derek
Team: Eric, Joel, Jamie, RyanC
Premise: Launch a high altitude weather ballon with video and still photo capabilities


We are going to launch a weather ballon to achieve three goals:

  1. Obtain pictures and video of St. Louis and the earth from high altitude
  2. Execute a well organized project to attract people to Arch Reactor
  3. Provide a good knowledge base and experience for future flights

A KCI1200 balloon is capable of reaching in excess of 90k feet.  We'll have a payload containing a still camera, HD video camera, high altitude GPS, cell phone to broadcast low level GPS and an Arduino logging sensor information.

Team Members

Derek, Eric, Joel, Jamie, and RyanC

Timeline and Milestones

July 30thGrant submitted to AR
July 12thGrant Approved
July 14thOrdered balloon,gps,phone and camera
August 2ndPostponed target date
 Passed HAM test
August 5thAll materials have arrived
August 13thTarget Launch Date
Sept. 11thNew target launch date with full moon


Weight Catalog

  • Parachute            68g
  • Video Camera  160g
  • Cell Phone          84g
  • A560 no bat       166g

Team Notes

  • Need to look into IR and blue filters
  • Moon path

    On Aug 13 the moon rises at 7:41pm and the sun sets at 7:58pm


    At 8:10pm the moon will be about 4.5 deg above the horizon.

    At 8:30pm the moon will be about 8.15 deg above the horizon.

    At 8:45pm the moon will be about 10.85 deg above the horizon.


    The moon will be approx 240,000 miles from St. Louis.   At 80,000 feet, your camera will only be 15 miles off the surface, which is a difference in angle of 0.006%.  So however far you want the moon off of the horizon in your pictures, you can safely use what you’d observe from the ground.





Antenna Stuff


APRS Notes:

FAA/Safety Related:

FLDIGI info:


Programming Notes:

<M0JSN> what did you use in the end?
<Upu> ong TEST=((float(LONGM)/60.0)+(float(LONGS)/3600.0))*1000000L;
<Upu> long TEST=((float(LONGM)/60.0)+(float(LONGS)/3600.0))*1000000L;
<Upu> sprintf(TELEMETRYSTRING,"$$AVA,%i.%06li",int(LONGDEC),TEST);
<fsphil> heck of a calculation lol


CHDK Script:

arch reactor balloon script v5
Authors: Arch Reactor Hackerspace (Jamie Bilinski, Derek Sigler, Eric Geldmacher, Ryan Castanho)
Tested on: A480 (Digic 3)

Uses propcase lib
@title ArchReactor Balloon Script
@param t Min Sec Delay between images
@default t 10
@param j Number of JPEGs/cycle
@default j 10
@param d Number of Raw/cycle
@default d 1
@param e EV Bracketing delta/6
@default e 4
param l est low alt mins
default l 45
param h high alt time mins
default h 110
param r est reenty time min
default r 185

h=((t-1)*1000)+930 --adjust for write time
if h < 9000 then w=9000-h else w=1 end --process delay ms after RAW shot

function flashoff()
 set_prop(142,2) --no flash
 while not get_prop(142) == 2 do
 return true

function setfocuslock()
 set_prop(6,3) --infinity
 while not get_prop(6) == 3 do
 return true

function snapraws()
 for i=1,d do 
   until get_shooting() == true
 return true

function snapjpgs()
 for i=1,j do 
   until get_shooting() == true
 return true

function snapevbrac()
 for i=1,e do
  if (evi-(i*32)) < 1 then set_ev(1) else set_ev(evi-(i*32)) end --may need in certain light?
  until get_shooting() == true
  until get_shooting() == true

--{{ Maybe next time!
function logtemp()
print get_temperature(0)
print get_temperature(1)
print get_temperature(2)

click("shoot_half") --in case A480 is in play mode
 play_sound(4) --beep each cycle so we know it's running
 until false
reboot() --meh


*replace "{" and "}" with right and left bracket


Notes from IRC:

<priyesh> on an NTX2, would you permanently keep the EN pin high or use the microcontroller to take it high only during transmission?
<Darkside> keep it high
<Darkside> we've found that fldigi demodulates RTTY better if theres a constant carrier
<fsphil> unless you're after power savings for a long flight, that's pretty much the only time you'd need to toggle EN
<Darkside> if you don't have it, it can loose the first few bytes as it synchronises
<priyesh> Darkside: ahh. thanks for the advice
<Darkside> sode*
<jgrahamc> On GAGA-1 I had EN tied on permanently because then it's easy to find the carrier.  Also, it doesn't draw much current and there's a 'startup time' whenever EN is enabled.


Posted by
Derek Sigler's picture
Derek Sigler
on Wednesday, July 6th, 2011
Filed under balloon
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  1. Build Night!
    • Start time: 07:00pm
    • End time: 09:00pm
    • Where: Arch Reactor, 2215 Scott Ave, St. Louis, MO 63103, USA
    • Come help build out Arch Reactor into the kind of space we all know it can be! All skill levels welcome, we can even teach you some new building skills!

    • View this event in Google Calendar

Friday, September 22nd

  1. 3D Printer Meetup

Saturday, September 23rd

  1. BoardGame Night * ArchReactor
    • Start time: 02:00pm
    • End time: 11:30pm
    • Where: 2215 Scott Ave, St. Louis, MO 63103, USA, Arch Reactor
    • Come On Out and Play games With us. If you don't know games that's OK we are friendly and love to teach. If you do, bring your Favorites along and let get a Game in.

      We'll have Food there, and I'll happily take 5$ in exchange for letting you eat all day.

      We start at Noonish and Play until you Leave or after Midnight, whichever comes last. :)

    • View this event in Google Calendar

Sunday, September 24th

  1. Synthesizer Meetup
    • Start time: 12:00pm
    • End time: 07:00pm
    • Where: Arch Reactor, 2215 Scott Ave, St. Louis, MO 63103, USA
    • ***Starts at noon, cleanup/breakdown begins at 6PM, please ensure we're all out of the building by 7PM***

      *** what it is:
      In the modular synthesizer world, there are an endless number of
      modules we'll never get to try and if we do, won't be able to afford - likewise with keyboard synths, VST instruments, effects and other gear like controllers. But in a meetup setting, we can come together and collectively explore.

      Our mission comes in a couple of different strands...

      1) the Eurorack modular community and other DIYers, especially those who want to get into building their own synthesizers. We can show you what's involved and help you move forward, in most cases quite realistically. We like seeing the modular family grow. There will be lots of modules on hand to demo, inlcuding an extensive DIY spread courtesy of Modular Addict (traveling all the way from Wisconsin no less...!

      2) keyboard synth users and DAW/VST-based musicians. No need to be specifically into modular to love synthesizers so all types are welcome. So many of us are islands, little project studios in bedrooms and basements - this is an opportunity to put names with faces and get an idea what's going on in our larger community, and get inspired to try new things from their examples.

      Everyone is encouraged to swap production tips, recording techniques, gain insights into an optimal workflow, and most of all... see/hear how we each make our music and sounds.

      Here's what we're going to do...

      1) talk shop - features, specs, deep patch design, demo your rig, maybe like walking around at NAMM or Musikmesse but more personal.

      2) connect to one of two open MIDI networks + small PA systems, start jamming and see where sit takes you.

      3) presentations. This part is still TBA, but I would assume there will be at least one person or group we may want to carve out a specific time for.

      *** how to participate:
      Bring your gear, and don't forget your power strips and extension cords, headphones, controllers, or anything else you'd need to make it work 100% without anything but tablespace and an electrical outlet.

      If you have a lot of stuff, be mindful of how much you bring. Tablespace is limited and priority will be given to modular equipment and/or to those who want to schedule a presention.

      If you've got teachable knowledge please consider presenting. We would love to "formally" make time for specific concepts, rigs or people who have something special to offer. Post your ideas in the group for consideration, and/or send a PM to Owen Godwin. There will be a limited number of slots for this.

      Invite your friends who'd be interested. There is a limit to how many the space can accomodate, so please have them RSVP to this event page.

      *** additional:
      Please be respectful of the space and clean up after yourselves!

      This event is graciously hosted by our friends at Arch Reactor, STL's hackerspace/makerspace. Please consider tipping them a couple bucks if you can. This isn't about making money nor are we requiring anyone to pay anything, it's just a suggestion since they are hosting us without charge and it's a great way to ensure the future of their facilitty/operations.

      Their website...

    • View this event in Google Calendar
  2. Hack Something!

Tuesday, September 26th

  1. Shop Training - Forge/Blacksmithing