Flight Announcement for EOSS-179

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

Flight Coordinator: Larry Cerney

LAUNCH DATE: July 28th, 2012 (wx delay +1 day)
LAUNCH TIME: 07:10 am MDT (13:10 UTC)
LAUNCH SITE: Windsor, CO (driving directions)

EOSS Flight Day Frequencies:

Tracking and Recovery Frequencies

Preflight Net:

  • 147.225 MHz 8 pm MDT preceding night
  • 146.640 MHz will serve as a backup frequency

Tracking and Recovery Operations

  • Repeaters 
    • 449.450 MHz (103.5 Hz Tone) RMRL
  • Field Simplex Frequencies  
    • 446.100 MHz simplex for field recovery operations
    • 446.150 MHz simplex for field recovery operations (Backup)
    • 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.


  • Launch Site Simplex
    • 146.550 MHz


EOSS-180 Balloon Payload Frequencies

  • Beacons
    • 147.555 MHz
    • CW ID: AE0SS
  • 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
  • no backup

EOSS-180 Student Payload Frequencies

  • 437.405 SSB CalPoly AFSK payload


Flight Systems: 


Balloon Manufacturer Totex
Balloon Type latex
Balloon Size 3000 g
Neck Load 13.1 Lbs.
Neck Lift 15.9 Lbs.
Ascent Rate 1329 fpm estimated
Estimated Burst Alt 108,000 ft. ASL
Descent Rate 950 fpm estimated
Parachute 10 ft.


Payload Configuration: 

Payload Experiment Designer

SGC - 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  

Breakfast for the trackers will be at the Windsor Launch site.   We will leave the launch site and go directly east to near Greeley.

Johnson's corner KB0YRZ and W9CN at 5am


Location Grid X Grid Y
Windsor Launch Point 20 30
Grid Test   40.75� N , 104.333� W 52.8 49.1


Tactical Call Signs

Tactical Callsign Name Notes
Alpha WA0GEH, KC0D Marty and Mark Tracking and Recovery
Bravo N0IX , Doug President, Tracker
Charlie W9CN Mike and Miles Trackers
Delta WB0DKT, KB6OKA Glenn and Edna Trackers
Echo N0NDM Larry Launch and Grab
Foxtrot KB0LP Dave Tracker
Golf KC0RPS, N0NFW Jim, George Tracker
Hotel KB0YRZ Chris Tracker
Papa AC0RY Brian Colorado Space Grant