Re: [GPSL] BUNS project update
- Hi Brek,
Glad you got your APRS module working OK.
Re the payload support. The 4-tube scheme works well, especially if
you have just the one payload, and the 4 support lines provide torsional
coupling to the parachute shroud lines.
But if you plan on carrying any other stuff lower on the string, especially
if it's heavy, then a single support tube thru the center works well,
since none of the payload line tension stresses the upper payload
structure. Separating payloads also does wonders for EMC problems, like
3rd harmonic of a 70cm ATV xmtr desensing the GPS receiver front end.
I think you'll find that a 300 mW beacon signal will be plenty strong
during flight - it is written: "Line of sight is a magic thing." It
may be a bit puny once the antenna is lying on the ground after landing,
however. One of our old-time members developed a self-erecting 2m ground
plane that keeps the radiating element aloft after landing, and the
trackers LOVE it! The only payload we've used it on is the crossband
repeater, tho, since it works only if the antenna is at the bottom of
the flight string. There's a pic on www.eoss.org somewhere under the
Hardware button on the home page. Be SURE to use RG-142 coax - PVC jacketed
RG-58 embrittles in the cold.
73 de Mike W5VSI, EOSS
Brek Brixius wrote:
> Hank and Group:--
> I ended up sending both my trackers back to their makers. Byon
> discovered that something had changed from his version of the Etrex to
> Mine. It was an easy fix. He told me what wires to swap and where to
> jumper and I have a working tracker :).
> Scott said the OT1x I sent back worked for him (after he fixed the
> voltage regulator I destroyed). He returned it to me. I'm still not
> able to get it to transmit unless I tell it to ignore the GPS lock. I'm
> not sure why. If nothing else, I figure I can use it as a beacon.
> My original airframe concept was a styro-cube with coroplast armor
> exterior and 4 through-tubes (one in each corner). I covered
> the coroplast with black foamies with a space blanket ring around the
> middle. It looks sharp but weighs over 3 pounds without any
> electronics. So, I am abandoning this design which I refer to as Skytanic.
> I have a new airframe in design that I am really liking. It looks like
> it will shake out much lighter and be easier to reconfigure as well.
> I bought a couple of log tags for temperature sensors. I was thinking
> one for internal and one for external. Now I'm thinking a log tag for
> external temperature logging and the OT1x beacon will send temperature
> data for the interior temp.
> I bought a lighter radio. An Alinco DJ-S11. It is handy for listening
> to the local net and I have been carrying it in my shirt pocket. It
> doesn't have much transmit range though. I hope changing the antenna
> will improve it a lot. The plan right now is to fly the DJ-S11 with a
> roll up j-pole.
> The local HAM club asked me to give a presentation for them. I showed
> them videos A and C from NSTAR's 2003 season DVD. Mark was kind enough
> to send that to me a few months ago. The guys enjoyed it very much. I
> chose to show them video C because it had landing footage. I think that
> put a lot of folks concerns to rest. Thanks Mark for sending the Video :).
> I have a ballistic nylon parachute on order from rocketman. I was not
> sure what size since I don't know exactly what I will be flying yet.
> Their suggestion was to order a larger size than I thought I needed and
> they have some sort of ring that slides up the lines and pulls the chute
> edges in. I am aiming to keep my new airframe under 4 pounds loaded. I
> think I ordered a 6 foot chute. I hope it will work.
> I haven't been spending all my time on the balloon project. Matter of
> fact, I have been spending a lot of time listening to HAMs on the CQ-100
> from QSONET.COM. If you haven't seen it, you should. It's a virtual HF
> rig. Really cool and you can try it free for 90 days.
> 73 everybody.
> */Hank <n1ltv@...>/* wrote:
> --- In GPSL@yahoogroups.com <mailto:GPSL%40yahoogroups.com>, Brek
> Brixius <gofly2007@...> wrote:
> > At any rate, I am addressing the GPS18 LVC, 5m problems
> > with the open tracker group.
> Brek is making good progress with his GPS18 with assistance
> from the <open tracker> group. He's now getting his GPS
> output displayed on Hyperterm which is always a simple but
> effective starting point.
> Thought GPSL group would like to know the above.
> We have the perfect Group for you. Check out the handy changes to Yahoo!
Mike Manes manes@... Tel: 303-979-4899
"Things should be made as simple as possible, but not more so." A. Einstein