Model Forum / General / Rockets / April 2004

There's the GPS attachment for the RDAS flight computer;
it's more than $100 but well under $750 IIRC; it's small
enough to fit in a rocket.

-dave w

Most of the GPS stuff out there are receivers; they calculate their
position and save it for later display or download; once you have the
rocket back. They are not meant as rocket locaters.

To find a lost rocket with an onboard GPS receiver, you'd also have to
have a telemetry transmitter of some type to relay the rocket's GPS info
(location) to something you can display it's location on. You would be
hard pressed to find a GPS telemetry system for $100.00

Try:

http://www.gpsflight.com/

Lots of info on GPS telemetry systems.

There are also combo FRS/GPS walkie-talkies which transmit GPS locations
to other FRS/GPS radios and display the position of the other unit. You
could fly one in a rocket, but I don't know about controling it.

Google for FRS GPS and see what comes up. I think they're more than
$100.00 each, though. :{

One option:

http://www.gpsflight.com/

  Just what size of a rocket are you trying to fit this into...?
Bear in mind, that you're going to be limited by the size of the GPS
antenna, the receiver, and whichever transmitter you use.

Hi Casey

Well, there are a few options out there now.  We (Atha Aerospace) have
been developing a system that interfaces with the FC-877 flight computer
but the GPS portion does not require the FC to operate and find your
rocket. The bonus with the FC-877 is you can get real altimeter data
back for immediate accurate altitude feedback.  It works very well.

We are in limited distribution at the moment with the locals trying the
system and software out and giving us some feedback.  We are using the
same designer and developer of the FC-877 for the AGTS system, Wayne
Hortensius.

You will need some ground support to receive and then walk to the
landing site.  There is software for the palm for cheap data
interpretation, along with pc software.

Check out www.atha-aerospace.com for the product.  If you need more info
contact us.  There is also lots of links and info on gps in general at
www.gpsinformation.net.

The next question is what size of rocket are you looking at?  We have
fit the Atha AGTS unit into a 2.1" airframe (some magic maneuvering is
required)  But a better option may be to use a beacon transmitter and a
sensitive receiver (still expensive but smaller).  Try
http://www.merlin-systems.com/falconry/ for the TX units and
http://www.wildlifematerials.com for the receivers.  You will have to
point and find with this system and it does have a limited ground range.

David Buhler

GPS is fine, but you can lose lock and the signal when the rocket
comes down on the other side of a sizeable hill or in an area covered
in thick foilage. A falcon tracking beacon is by far the easiest
solution. The beacons cost between $100 and $150. The reciever cost
about $300 with yagi. The good news is that with a little practive you
will always find your rocket.

A simple GPS system would be the Garmin Rinos. You can disassemble one
and they will fit into some very small airframes. The nice part is
that they querry each other and you can see exactly where the unit is
relative to your position with a map to guide you. The 110 units are
cheap. I use 110s for throwaway and the 120s for the tracking unit.

Arnold