There is also the new ARTS GPS system at
However, I don't think these are what he's asking about as neither will
do the 10-20Hz sample rate. I have seen a unit that will do 10Hz, but I
can't find the data sheet right now. I'll keep looking. It wasn't
insanely expensive, IIRC, but was certainly more than the 1Hz units.
Also there is an angle here nobody in rocketry has grasped.....
HAM's like to fly balloons.
HAM's like to play with electronics.
HAM's like to recover the payload from the balloon that went over 100,000'
So they have all kinds of neat things like landing location prediction
And free GPS transmitter designs good to over 100k.
But we here in rocketry land try and reinvent the wheel.
My next high altitude flight is using a PICO Beacon:
APRS was practically designed for rocketry.
True, but the cost of entry on a HAM license is dirt cheap -- $25 for
the study guide (although you can do it online if you want) and $14 for
That's $39 more; I'm still way ahead cost-wise against anything else on
There are three levels of ham license -- Technician, General and Extra
(if I remember the current names correctly).
It costs $14 for a testing session; you can take one or more exams at a
session. Technician is the "lowest level" and requires part 2 (no CW).
General and Extra both require part 1, which is CW.
For the BeeLine stuff, you just need a Technician license. The hardest
part of it is staying awake through the book.
And unfortunately careful reading of the FCC rulebook gives no
indication that rocket use is ok in many of these bands that are
reserved for animal tracking and the like, they are quite specific and
to possible uses, and hence I believe popular products like
rockethunter etc are in fact not legal.
Really? OK, here's a scenario:
I plan to track an animal. I want to photograph its habitat from the
air. I'm going to use a rocket to do this. I need to make sure I don't
lose my rocket. In order to make sure that I don't lose it in the
field, I have to 'practice' with it in other areas.
Or same as above, but I'm planning on selling my rocket to animal
Read the FCC rules. This is not a valid scenario. Why PO the FCC when
we're already fighting the ATF? Let's (as a hobby) next allow breaking DOT
rules. I'm sure that will back the case that the hobby is regulating!
After careful thought and consideration, I invested in BRB transmitters and
a Ham (Technician) license. It took a few hours to study for the exam,.
However the exam itself was quite easy and inexpensive> I had already
ordered an inexpensive single band Transceiver prior to taking the test.
Once I began studying, I realized I wanted the ability to do more with my
handheld and immediately ordered something better.
Furthermore, the BRB system is much more flexible (programmable) and cost
effective than the competitors.
Mark A Palmer
Why do you want a 10-20Hz sampling rate? If you're wanting to log
vertical velocity type information (either from a vertical velocity
output or a delta-z determination), I don't think any comsumer GPS
systems have algorithms that can reliably determine vertical velocity
AND rapidly changing altitude at even 1Hz. Now, once a rocket is
slowing and coasting up to apogee, the GPS can probably determine
altitude more reliably. Anything during the thrusting period is
probably not reliable with consumer units.
Secondly, all the consumer GPS units I've seen specs for use 1Hz. If
you wanted a 10Hz sample rate, you'd need to either increase your baud
rate and/or limit the number of NEMA sentences you're sending. And
there's really not a big consumer market for GPS units that need
location/altitude data at a rapidly changing rate.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.