Re: Wanted: Payload recovery team for GPSL

Michael Hojnowski


The flight will have three identical trackers.  They're all APRS "Peach" trackers, originally designed by Alan Adamson, W7QO, though built by me and some Cornell students.  They're running with 1/4 wave dipole antennas and measured at about 15mw.  I've flown 12 of my own payloads with these trackers, and assisted in a half dozen other flights with them.  I've never lost a flight using these trackers, aside from that last drop payload that ended up in a lake.   That said, they're 15mW.  It takes skill to track and recover them.  It's usually advisable to have someone near the predicted landing zone as it descends.  If they're in a tree, you'll hear them easily a mile away.  If they're on the ground, it could be 1/4 mile or less, depending on terrain.  On one recovery, I had to unsquelch my radio and listen for squawks and driving around doing crude "rdf" until they were loud and clear enough to decode.  I know I'm a whacko, but in my opinion, that adds to the fun and challenge of the payload fox hunt.  Since the payloads belong to me, I can take that chance.  For other groups, we usually supplement with a SPOT or something.

I'd prefer to chase my main payload, since it'll have hundreds of dollars of additional electronics on it.  I wouldn't want to put the "declared lost" responsibility on anyone but myself.  The drop payload I'm requesting help for will just be the stuffed animal with a tracker, which costs me about $50 to build.  If we can't find it, "oh well".  I'll spend more than that on gasoline on the chase day.

Anyway, the payload I'm requesting help for is simply a fun and silly little experiment.  No harm, no foul if lost, or if people aren't interested in chasing it.  I can always backtrack to look for it after my main payload recovery.


On 5/19/2019 9:46 AM, Nick wrote:

When you say a "tracker" can we assume that includes a GPS, APRS processor like a TinyTrack3, a transmitter of some power (we chased a 50 mw transmitter once that was a giant waste of time), and a reasonable antenna and that the package has flown before and/or had a reasonable amount of testing?

Would you consider chasing and recovering the secondary and let another group chase and recovery the main payload?


-----Original Message-----
From: [] On Behalf Of Michael Hojnowski
Sent: Saturday, May 18, 2019 20:33
Subject: [GPSL] Wanted: Payload recovery team for GPSL


I'm intending to reprise a launch of the payload we launched at Cornell
a few weeks back. It features a DTMF triggered secondary payload
release (the last one was a little Cornell Big Red Bear) with Parachute
and tracker. We attempted to release it at 90,000 feet but our DTMF
decoder didn't quite get the message. A failsafe dropped the bear from
95,000 feet. Unfortunately, the Bear got a little waterlogged prior to
flight (it was drizzling rain) and fell faster than predicted right into
Cayuga lake. It's sleepin' with the fishes.

I want to make another attempt with a, hopefully, better outcome. Since
the dropped payload follows its own trajectory, I would need to have a
second team attempt to recover that payload while I chase down the main
payload package. If anyone is free to chase the drop payload, I'd love
the help. It's not going to be especially valuable, just a tracker and
some token item on a hand-made parachute, so I won't cry if it goes

If interested, please let me know!
Mike / KD2EAT
Advisor, Amateur Radio Club at Cornell

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