Announcement of EOSS-124/125

LAUNCH DATE: November 10, 2007

  • EOSS-122 - 07:30 am MST (14:30 UTC) CU Gateway
  • EOSS-123 - 08:15 am MST (15:15 UTC) Bacteriological Sampler

LAUNCH SITE: Windsor, CO (directions)

Pre-Flight Information

On Air Nets

Check into the weekly EOSS net every Tuesday evening, except the 2nd Tuesday of the month when we hold our face to face meetings.

  • Tuesdays at 8 PM (20:00) Local time
    • 147.225 MHz 107.2 Hz tone CRA Repeater (Denver)
    • 145.460 MHz 107.2 Hz tone CRA Repeater (Boulder) manual link required (link may be unavailable)
    • 145.160 MHz 107.2 Hz tone CRA Repeater (Colorado Springs) full time link active
    • 146.640 MHz backup DRL Repeater (Denver only)

Pre-Flight Coordination Net

The evening prior to flight we hold a coordination net at 20:00 Local Time to assign the grid information and tactical callsigns. Any last minute information, launch time changes, launch location changes, maybe even a cancellation will be announced on this net.

  • Preflight Net:
    • 147.225 MHz 8 pm Local Time the evening preceding the flight
      • 145.160 MHz simulcast in the Springs
    • 146.640 MHz will serve as a backup frequency

Tracking and Recovery Team
Flight Day Breakfast

  • McDonalds in Fort Morgan
  • Breakfast starts at 6 am
  • Depart to recovery positions 6:45 am

EOSS Flight Day Frequencies:

Global Frequencies

EOSS-124 Balloon Frequencies

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

EOSS-125 Balloon Frequencies

  • Beacon
    • 145.600 MHz
      • ID: K�ANI in CW
  • APRS
    • 144.340 MHz
      • ID: KC0YA-11
      • DIGI: EOSS
      • 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
      • Telemetry once a minute
      • Sample Data
  • 145.600 MHz
  • ID: K�ANI-11


Radio Coverage:

Green, you should be able to work the payload systems.

Red, is the border of the received signal. Red appears jittery because it is depicted topographically. Thus, the red dots on the eastern half of the map but well within the maximum distance show hilly terrain behind (east) which reception is not possible.

This is a generic 95,000 ft ASL coverage map for flights that depart from the vicinity of our launch site. Flight day coverage may vary depending on upper air winds.

Flight Systems:


Balloon Manufacturer Kaysam
Balloon Type latex
Balloon Size 3000 gram
Payload 25.6 lbs.
Free Lift % calculated at fill
Ascent Rate 1100 fpm estimated
Descent Rate 950 fpm estimated
Parachute 10 ft
Peak Altitude determined after flight
Launch Conditions determined at launch



Balloon Manufacturer Kaysam
Balloon Type latex
Balloon Size 3000 gram
Payload 26.5 lbs.
Free Lift % calculated at fill
Ascent Rate 1100 fpm estimated
Descent Rate 950 fpm estimated
Parachute 10 ft
Peak Altitude determined after flight
Launch Conditions determined at launch


Payload Configuration:

Tracking and Recovery Info:


Location X Y
Rt 71 & 14 (West Intersection) 53 45
Touchdown (see Prediction Page)


Tactical Callsigns

Tactical Callsign Name Notes
Alpha WG0E and KB0YRZ Colin and Chris Tracking and Recovery Coordinator
Bravo KC0RPS and N0SSW Jim and Harlan  
Charlie K0SCC Steve  
Delta WB0DKT,KG6HXM, KC0ZIE,  WB6DKF Glenn,  Sam, Darren, and Heather and Steve Dean  
Echo AC7FY Clint  
Hotel KC0UUO and N0NDM Rob and Larry  
India KC0WWJ and K2CUI Brian and Michaela  
Juliet AE0SS Nick Ground Station


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.

Experimental Systems

EOSS-124 - CU Gateways Program

no detailed info

EOSS-125 - Atmospheric Bacteriological Sampler

The Bacteriological Samper
L to R Robert Lossing and Co-Investigator (???) fills here folks - Thanks


by Mike Manes, W5VSI

The purpose of this experiment is evaluate the DNA of any bacterial species appearing in the upper atmosphere.  The sampler comprises a 1 litre/min vacuum pump which draws ambient air in though sterilized 1/2" iron pipe and solenoid valve, then through a 0.2 micron filter. The pump's exhaust is vented to the exterior of the 19 lb package.

Prior to launch, the pipe is heated to over 130C using AC power, and during ascent by battery power.  This destroys any low-altitude contaminants.

At 30,000 ft MSL, a baroswitch closes causing the heater to be turned off, the valve to open and the pump to run.  A timer shuts everything down 60 minutes after the sample run started, or at about 90,000 ft, assuming a 1000 fpm rate of ascent.  Once shut down, the solenoid valve prevents contaminants from entering the filter.  On recovery, the filter is removed, sealed and placed on dry ice until it can be opened in the sterile environment of the the lab at CU.

note: customers are welcome to submit detailed synopses of their flights or web links to their own web sites.