Flight Announcement for EOSS-185/186

Recap Maps | Frequencies | Flight Systems | Payload Config | I-Gates | T & R | Text Recaps | Photos | Audio | Video | Data | Charts

Flight Coordinator: Jim Langsted, KC0RPS
LAUNCH DATE: April 13th, 2013 (wx delay +1 day)

  • LAUNCH TIME EOSS-185: 6:50 am MDT (12:50 UTC)
  • LAUNCH TIME EOSS-186: 7:10 am MDT (13:10 UTC)

LAUNCH SITE: Eaton, CO (driving directions to Eaton Launch Site)

EOSS Flight Day Frequencies:

Tracking and Recovery Frequencies

Preflight Net:

  • 147.225 MHz (107.2 HZ Tone) CRA Repeater, 8 pm MDT preceding night 
  • 146.940 MHz (103.5 HZ Tone) RMRL Repeater if the CRA machine is down
  • 146.640 MHz will serve as a backup frequency

Tracking and Recovery Operations  

  • Front Range and out east 
    • 449.450 MHz RMRL (103.5 Hz Tone)
  • Sterling

    • 145.295-, NPL May be off air, try 147.500

  • Holyoke

    • 146,955-, NPL

  • Ovid

    • 146.655-, NPL

  • Akron

    • 145.600-, 123 Hz PL

  • Field Simplex Frequencies   
    • 446.100 MHz simplex for field recovery operations for EOSS-185
    • 446.150 MHz simplex for field recovery operations for EOSS-186
    • Note: Some radios insist on incorrectly placing a negative 5 MHz offset when selecting frequencies from the simplex portion of the 70 CM band. Check your radio and if this is the case. Consider programming in this simplex frequency to a memory channel as some radios have demonstrated the annoying habit of re-inserting the offset if you momentarily shift to a repeater then return to the simplex freq. Check the operation of your radio on this simplex freq to be ready for however your radio behaves.
    • 146.550 MHz Backup field simplex
  • Repeater Coverage Pages - Listings of all repeaters available in the expected flight areas.
  • There may be FRS operations see THIS PAGE for a list of channel numbers and their associated UHF Frequencies.

Ground Stations Frequencies

  • Launch Site Simplex
    • 146.550 MHz
  • HF - Possible ops
    • 7.235 LSB


EOSS-185 Balloon Payload Frequencies  

  • Beacons
    • 147.420 MHz
      • CW ID: K0SCC
  • APRS
    • 144.340 MHz
      • ID: AE�SS-11
      • DIGI: EOSS
      • Node: BALNOD
      • APRS Time Slotted Every 30 seconds at 0:00 and 0:30
      • power up at 58 seconds past the GPS minute to properly slot telemetry
      • Telemetry once a minute
      • Sample Data
  • 147.420 MHz 
  • ID: K0SCC-11
  • slotted 15 and 45 after the minute

EOSS-186 Balloon Payload Frequencies  

  • Beacons
  • 145.600 MHz
  • CW ID: W5VSI
  • APRS
  • 144.340 MHz
  • ID: KC0YA-11
  • Node: BALND2
  • APRS Time Slotted Every 30 seconds at 0:15 and 0:45
  • power up at 13 seconds past the GPS minute to properly slot telemetry
  • 445.975
  • KC0UUO-11


Flight Systems: 


Balloon Manufacturer Totex
Balloon Type latex
Balloon Size 3000 g
Neck Load 21.2  Lbs.
Neck Lift 25.4  Lbs.
Ascent Rate 1329 fpm estimated
Estimated Burst Alt 101,000 ft. ASL
Descent Rate 950 fpm estimated
Parachute 8.5 ft.


Balloon Manufacturer Totex
Balloon Type latex
Balloon Size 3000 g
Neck Load 21.0  Lbs.
Neck Lift 25.1  Lbs.
Ascent Rate 1329 fpm estimated
Estimated Burst Alt 101,000 ft. ASL
Descent Rate 950 fpm estimated
Parachute 10 ft.


Payload Configuration: 

Payload Experiment Designer

Space Grant Consortium Demosats

Experimenters are welcome to submit websites for linking or overviews which I will post on a page on the EOSS website.

Internet Gateway Stations:

Future I-Gaters:

EOSS is always in need of I-Gate stations. Check out the EOSS I-Gate page for information on how to participate and why we need you.

Current I-Gate Station:

If you are present at your iGate during the flight try and monitor the tracking and recovery frequency. The ground station likes to check the frequency prior to launch to find out if any stations are out there ready to igate the traffic onto the net for the FAA to monitor.

The prediction program used to determine the track of the balloon prior to flight can now output a prediction for the Rise, Closest Approach, and Set of the balloon for each of your stations. I have posted a prediction page for stations that I have been able to discover geographic coordinates. See the I-Gate prediction page for an example. The page will not be updated daily, however, it will be updated the evening prior to flight for I-gate planning purposes.

I have often been asked by iGaters when they should expect to either start receiving signals (AOS) or expect to see those signals disappear (LOS). This prediction page should answer all those questions for you.

Your Log Files

Our technical committee members would also request you open a log file and record all the packets you hear and forward onto APRS-IS. Whenever there is a technical failure of a package it is always helpful to have the most complete dataset possible to attempt to determine the cause of failure and possible fixes. After a flight send your data files to me (webmaster) and I will distribute them to the appropriate payload builders. They appreciate these logs even if all goes fine during a flight.

Tracking and Recovery Operations

The T&R Coordinator's Notes:

Hello Trackers!

Thanks to everyone for stepping up to this very long tracking adventure.  We will be flying two 3000 gram balloons and hosting over 100 students.  We have a great crew and I am sure we will be successful. 

Some trackers will advance to the launch site where there will be some breakfast bagels at the launch site.  Or they can stop in at Johnson�s Corner for those great cinnamon rolls.  For the folks moving towards Sterling on I-76, look to meet at McDonalds in Ft. Morgan sometime about 5:30-5:45.  Be sure to finish up and get on the road by 6:15 as we may have a long way to go from there.  Mark and I will not be joining you at McDonalds as we are going to be booking it to the field and we will meet up with you there. 

Be sure to fill up with gas Friday night, bring warm clothes, water and munchies.  Bring tow ropes if you have them. 

The pre-flight net will be hosted by John, KC0L at 8:00 on Friday.  CHANGE HERE!!!  This net will be on the 146.94 PL 103.5 RMRL machine.  Thanks to John for running the net.  Let�s all give him our support.


Tracking and Recovery Grid  


Grid X

Grid Y

Last Chance



Grid Test   40.50� N , 103.25� W




Tactical Call Signs


Call sign





Marty, Mark

Tracking Coordinators



Rob, Doug

Tracking, Recovery



Steve, Rick and Parker

Tracking, Recovery, plus 2



Jim and Harlan

Co-FC, Tracking, Recovery

Foxtrot KB0LP Dave

Tracking, Recovery




Launch Coordinator and Tracking



Mike, John, Miles

Tracking, Recovery

India KE7KCK Tom

Tracking, Recovery (New Call)

Juliet KC0L John Tracking, Recovery (From Dallas)
Kilo KD0SEM Dave and Cheryl Tracking, Recovery
Whiskey KD0NRY Chris Koehler Colorado Space Grant