brainwagon "There is much pleasure in useless knowledge." — Bertrand Russell

4Apr/091

Beacon Gremlins

I was having some difficulty spotting my beacon: both on WA0UWH's grabber, and via WSPR spots. I figured that maybe my jury rigged antenna had fallen down, or I had some kind of similar hardware failure. Oddly though, my receiver seemed to be going strong.

I went over to my setup, and found that the power meter on my FT-817 was indicating basically no power going out. A few more minutes of checking cables and the like found out that my laptop had somehow muted its audio output, and therefore, wasn't sending any signal out. I groaned, cranked it back up, and then verified it was putting out a signal, and went to bed.

In the morning, no WSPR spots remotely. None.

I was puzzled, until I thought to check the time on my laptop. Oddly, it was about 23 seconds off. WSPR is synchronized so that you transmit on even number minute intervals, and if you are more than a few seconds off, it won't find you. The odd thing? I run the Network Time Protocol on my macbook: it should keep perfect time! I killed off the ntpd daemon, and it restarted, and was then resynchronized. I'm back to normal operation.

Filed under: General 1 Comment
4Apr/091

Open Tracker+ ordered…

ot1plus-assembledI have been trying to start a project to do a high altitude radio balloon launch. Toward that end, I ordered myself a Open Tracker Plus kit from Argent Data Systems today. It seems like a pretty trivial thing to tack together, and includes a nice little plastic case, so it should be good. For a balloon launch, I'd probably use the tiny surface mount version, but I figured this would be better for experimenting with, just to get the hang of the firmware and the like. The Open Tracker has some basic data telemetry functionality, and I could experiment by rigging some temperature and voltage sensors and play with that.

Addendum: I noticed this morning that WB8ELK was planning to launch not one, not two, but three separate balloons near Huntsville this morning. The first two were cut down at around 40,000 feet, but the third went to burst altitude. I was watching the paths of these birds intermittently via APRS on the internet, and was amazed at the speed these things get through the jet stream. KG4WSV-13, the highest balloon reached speeds of 130 MPH. Amazing.

Here are some links to the paths of two of the balloons as I tracked them via APRS on the internet:

KG4WSV-12
KG4WSV-13

Filed under: Amateur Radio 1 Comment
1Apr/091

3000th Post! And Gratzel Cells…

Wow.... this is the 3000th post that I've made to my blog since it's inception. Huzzah.

I really need to get a hobby.

In any case, Bill Meara over at the Soldersmoke blog mentioned this video about constructing solar cells from donuts and tea.


httpvh://www.youtube.com/watch?v=bVwzJEhMmD8

It sounds like a joke, but it's not. It turns out that powdered donuts aren't just white because they have powdered sugar on them, but because they also contain titanium dioxide. Who knew? You can read about them on Wikipedia.

Filed under: Science 1 Comment
1Apr/090

Nice signals over to W1BW this evening…

I was getting some pretty good SNRs into the east coast this evening, so I set my MEPT beacon to SMT Hellschreiber mode. Here's the clearest signal I've seen to date from W1BW:

smt

Filed under: Amateur Radio No Comments