EOSS-283 Qualification Flight Recap

EOSS-283 was launched from Windsor Colorado on 3/10/2019 with six EOSS beacons.  All payloads were recovered just north of the Colorado state line in Nebraska, near Peetz, Colorado.

This flight was particularlly challenging from the beginning because of multiple postponements due to the weather.  Finally, we had a calm day, no extremely cold weather or snow, and a resonable flight prediction that showed landing in the state of Colorado.

We flew 8 EOSS payloads for qualification testing, 6 of which were transmitting on different frequencies.  This turned out to be an excellent flight to start testing the new SDR systems that can receive all the payload frequencies simultaneously.  All of the payloads successfully transmitted their position through the flight.  The new 'bottom' transmitted OK, but it did not digipeat as it should.  This payload is qualified as a non-digipeating bottom, but will need to be requalifed for a digipeating bottom.  KC0D-14, a new 'top' worked fine. We were able to command a tetherd release and to digipeat through it. This payload is now qualified.  KC0D-2 lost the Bluetooth connection with its wireless release right after launch and did not recover.  Therefore the commanded release did not work.  The payload performed fine otherwise.  A change has been made to the firmware to address recovery from this type of situation.  Why it lost the connection in this manner is still unexplained.  This payload/release pair will need to be requalified.

After landing the flight string was drug though the mud for ~200 Ft (per the GPS data) due to the high winds at the landing site. None suffered significant damage, although they came back scratched and muddy.  Thank you to our trackers for getting there quickly to prevent further damage.

All in all, we had a great (long) day.  It was excellent practice for the upcoming flight season that starts in a week.  Thanks to everyone for your patience with the weather delays and for participating in this flight.

Mark - KC0D - EOSS Payload Team

Original Announcement: 

Update 08:40AM 3/7/19 Launch moved to Sunday March 10th from Windsor due to high windsDue to forecast high winds at the launch site, EOSS-283 has been moved to Sunday March 10th from Windsor.  This is also a change of launch sites.  Please note that Daylight Savings Time starts on Sunday so the launch will be essentially 1 hour earlier.The prediction for this flight can be found here. Further details with weather observations may be found at http://wxqa.com/eoss283.htmlA 1500g balloon flown for the qualification of multiple EOSS payloads.  

Event Date: 
Sunday, March 10, 2019 - 00:00
Flight Coordinator: 
Mark Patton - KC0D
Launch Site: 
Rt 71&14 West, X=65, Y=35, test N40.5000, W103.250 = 87.4, 27.6

EOSS-283 Qualification flight

This will be a flight of a single 1500g balloon in order to qualify EOSS payloads for future flights.

Balloon Type: 
1500g latex
8.5 ft
A list of Call signs and frequencies for the beacons on the EOSS payload string.
144.905K0SCC-11APRS/Cutdown/DFTop of record
144.340AE0SS-13APRS/DigiBottom of record
145.535KE0BMV-11Under qualification as top (APRS/Cutter/DF)
145.765KC0D-14Under qualification as top (APRS/Release/DF)Paired with tethered wireless release Alpha
145.645KC0D-2Under qualification as top (APRS/Release/DF)Paired with tethered wireless release Baker
144.360K0SCC-14Under qualification as bottom (APRS/Digi)

EOSS Preflight Net @ 8 PM MDT preceding night:
        • 449.225 MHz (-5 MHz Offset, 141.3 Hz Tone )  RMHAM Repeater  
        • 146.940 MHz (-600 KHz Offset, 103.5 Hz Tone) RMRL Repeater if the RMHAM machine is down
        • 146.640 MHz (-600 KHz Offset, 100.0 Hz Tone) DRL Repeater will serve as a backup to the backup repeater 

Launch Site:
        • 446.050 MHz Simplex  
        (Note that some radios assume these are repeater frequencies and attempt to put a 5 MHz offset in the transmit frequency automatically)

Track & Recovery Operations:
        • 449.450 MHz (-5 MHz Offset, 103.5 Hz Tone) RMRL repeater (Assuming we are flying out of Windsor).
        • 448.450 MHz (-5 MHz Offset, 100.0 Hz Tone) PPFMA repeater (Assuming we are flying out of Deer Trail).

        Simplex Frequencies:
        • 446.100 MHz Balloon #1 Field Simplex 
        • 446.275 MHz Car to Car drive out Simplex
        (Note that some radios assume these are repeater frequencies and attempt to put a 5 MHz offset in the transmit frequency automatically)

        Legacy 2M Simplex Frequency (not generally used due to desense/interference issues with the 2M APRS packets)
        • 146.550 MHz Simplex

DMR will be used when we run out of range to communicate between the trackers and the gound station.  RMHAM wide will be used for drive out frequencies.  There is a new DMR node at Akron.  The information below regarding the No CO repeaters.  Rocky Mountain Ham Code plug samples can be found at this link:  RMHAM Sample code plugs


Northern Colorado Regional Network (No CO) – Talk Group 721

A regional network supporting Northern Colorado is established using Talk Group 721. No Data or Texting. Repeaters supporting this talk group are:

Akron Akron 443.175 MHz 448.175 MHz 7 2 Operational – Linked
Boulder Lee Hill (RMHAM network) 441.9875 MHz 446.9875 MHz 7 2 Operational – Linked
ChyWy RMHR South Cheyenne 444.9375 MHz 449.9375 MHz 7 2 Operational – Linked
Fort Collins Horsetooth Mountain 441.7500 MHz 446.7500 MHz 7 2 Operational – Linked
Fort Morgan Fort Morgan EOC (mixed mode) 443.2000 MHz 448.2000 MHz 7 2 Operational – Linked

2M Direction Finding Frequencies:

  • 144.340
  • 144.360
  • 144.905
  • 145.045
  • 145.535
  • 145.645
  • 145.710
  • 145.765


Tactical Calls: 
TacticalCall SignNameNotesDMR
AlphaWAØGEH, KCØDMarty, MarkTracking CoordinatorsYes
BravoW9CN, WA6RNUMike, StanTrackers, Alpha BackupYes
CharlieKCØRPS, WØNFWJim, GeorgeTrackersYes
DeltaKØSCCStephenLaunch. TrackersYes
EchoKEØORBJohn, NancyTracker
Ground StationKB0TVJ, N2XGLRuss, Randy, JeffGround Station, Jeff Sunday OnlyYes
HotelKE7KCKTomFC, Launch, Tracker
IndiaWB0DKT, KC0ZIEGlenn, DarrenLaunch and Tracker
JulietKD0SEMDaveLaunch, TrackerYes
KiloN0NDM, N0LPLarry, Nick, ElijahLaunch, Tracker Only Sat
TR Breakfast: 
Grid Posted. Breakfast at Drover's in Brush, 28601 US Highway 34, Brush, CO 7:00 am. See new Grid Location due to Launch site change.