Archive for month: December, 2010

It receives!

December 29, 2010 | Amateur Radio | By: Mark VandeWettering

Well, I found a BNC connector, hooked up my antenna, and voila! Before testing it, I tried listening up on my FT-817, and the band seemed pretty dead. But the DC40B had signals! First powerup of my DC40B I can hear a bit of hum, which I suspect will only get better once I use […]

DC40B, Day 4 + over a year…

December 29, 2010 | Amateur Radio | By: Mark VandeWettering

Back in October of last year, I was eagerly putting together one of Doug Hendrick’s DC40b kits, a nifty little transceiver, complete with a nice metal case. Here’s where the assembly got to prior to today: brainwagon » Blog Archive » DC40B, Day 4, and stupidity on my part…. Yes, I didn’t install a chip […]

Jupiter, the Bringer of Jollity

December 25, 2010 | Astronomy | By: Mark VandeWettering

Phil Plait dug out these amazing pictures taken by Damian Peach. If you go to your local library and look at astronomy books that were published when I was a kid, you’ll see no pictures like any of this. The combination of both computer algorithms and video hardware has put the ability to take astonishingly […]

Merry Christmas to All…

December 25, 2010 | Merry Christmas | By: Mark VandeWettering

Well, it’s just after midnight, and with it is time for me and Carmen to don kerchief and cap and then to settle our brains for a long winter’s nap. To all my family, friends, and readers, I’d like to wish you all a Merry Christmas and Happy Holiday. Tomorrow, there will be prime rib […]

Android In Spaaaace!

December 22, 2010 | Amateur Satellite, Amateur Science | By: Mark VandeWettering

I tweeted this earlier, but in case you aren’t subscribed to my twitter feed (user brainwagon) then you should check it out: some Google engineers sent one of their mascots to over 100K feet altitude along with several Android phones to record the experience. The video is awesome. Android In Spaaaace! – Official Google Mobile […]

Apollonian Gasket

December 17, 2010 | Math | By: Mark VandeWettering

It took me an embarrassingly long time to write a program to generate this fractal known as the Apollonian Gasket: More information here: Apollonian gasket – Wikipedia, the free encyclopedia Each circle is labelled with its curvature (which is simple the reciprocal of the radius). In this particular instance, all the curvatures turn out to […]

Total Lunar Eclipse

December 16, 2010 | Astronomy | By: Mark VandeWettering

On Monday, December 20th, we’ll have an opportunity to view a total lunar eclipse. Huzzah! It’s been quite a while since I’ve had the opportunity to view one. According to this NASA eclipse calculator, the moon should enter the penumbra of the earth at 9:29PM Pacific time, with the partial eclipse beginning at 10:33 and […]

You can tune a banjo, but you can’t tuna fish…

December 16, 2010 | diy, Music | By: Mark VandeWettering

Or can you? Courtesy of the Make Blog, here’s an interesting little musical instrument called a “canjo”, a two string banjo that uses an old 4″ tuna fish can as the resonating cavity. Perhaps I should take a break from my plinky string sounds generated with software, and instead do it the old fashioned way. […]

Ground tracks of satellite passes…

December 14, 2010 | Amateur Satellite, Amateur Science, My Projects | By: Mark VandeWettering

Every once in a while, I feel like making high quality pictures of ground tracks of satellites. The Generic Mapping Toolkit is handy, especially when combined with the pyephem library. The thick line is the ground track of the amateur satellite AO-51, at any point in its next pass where it is visible from my […]

What ideas infect my brain and why…

December 13, 2010 | Rants and Raves | By: Mark VandeWettering

Some of you might be wondering what it is about this Karplus-Strong algorithm that has got me interested. Of course, long time readers of my blog might well have wondered that about any of a number of things that I’ve written about. What is it about checkers that prompted me to write a checkers program? […]


December 13, 2010 | Music, My Projects | By: Mark VandeWettering

Okay, I finally found my copy of Ken Steiglitz’s A DSP Primer (a great book, but sadly more expensive now than when I got my copy) and read through the implementation of the tunable plucked string instrument. A couple of things really need to be added: first of all, I was off considerably in my […]

An AO-51 recording, and an attempt at a QSO…

December 12, 2010 | Amateur Radio, Amateur Satellite | By: Mark VandeWettering

Well, it’s been quite some time since I tried to work any of the FM birds, but I dusted off my TH-D7A, my voice recorder and my Arrow antenna, and decided to give it a go. It was pretty busy, and as usual I found it a bit difficult to get in. I got myself […]

NanoSail-D Update

December 11, 2010 | Amateur Radio, Amateur Satellite | By: Mark VandeWettering

It appears that the solar sail cubesat NanoSail-D that was recently launched may not have deployed properly: they haven’t been able to track it or contact as of yet. Bummer. I’ve been intrigued by solar sail technology for quite some time. Here’s hoping they figure out what went wrong, but bummer thusfar. NanoSail-D Mission Status […]


December 9, 2010 | Music | By: Mark VandeWettering

The other day, I was trying to remember how to generate some simple sounds with minimal amounts of code. I remembered vaguely something called the Karplus-Strong algorithm, and it has been floating around in my head that I should look it up again. I mentioned it to Tom, and he spent 15 seconds drawing something […]

Congratulations to SpaceX, and a new Cubesat!

December 9, 2010 | Amateur Radio, Amateur Satellite, Amateur Science | By: Mark VandeWettering

Lost in yesterday’s thrilling launch of the SpaceX Falcon-9/Dragon launch was that during their flight, they also apparently deployed a cubesat: CAERUS (which is apparently Greek for “opportunity”). It has a 900mw FM AFSK beacon downlink on 437.600, and operates under the amateur callsign KJ6FIX. I have not as yet been able to locate TLEs […]