brainwagon

Well, I decided to give NOAA 18 a try during a nice 18 degree pass. The resulting image was actually pretty good, although still spoiled in spots by some nasty interference (some of which sounded like a phone ringing, very odd). Still, I think this is th first image that I had that made it […]

Well, I was playing around with cocoaModem a bit more, and decided to try to decode some of the HF-FAX images sent by the station here in Point Reyes. The quality isn’t quite what I would imagine it should be, and there were a number of sync issues, so I’m not sure what’s going on […]

Got on board the late night pass for the ISS, and right after that went down, turned around and worked SO-50. Sadly, the recorder I normally used didn’t pick up the passes, must have hit the stop button (annoying!). But I worked N6RSX via the ISS, then got KB7F and … rats.. memory… failed me… […]

I think this was the best ad during the Super Bowl (which actually for the first time I think eclipses the advertising spectacle that is the Super Bowl). YouTube – FedEx 2008 Super Bowl Ad

Another signal processing link that I think I need to understand: Overlap-Add STFT Processing

I still read stuff that isn’t radio relate. Some of it I’m sure most of you wonder “what kind of a nut are you, that you are interested in that?” Oh well. Here’s more reinforcement for the idea that I find crazy stuff interesting: a bunch of articles on models for snowflake formation: Gravner-Griffeath Snowfakes

Well, the price of launching a satellite for real is still way too high to be even an insane possibility, but there are some fun things that a space minded individual or club can do: notably, high altitude balloon launches. Witness this one, which came across the Make Blog today. It includes some pretty nifty […]

This just came across the amsat-bb mailing list: Since AO-16 was recovered approximately 6 months ago, the command team has attempted to reload the satellite software almost a dozen times without success. Subsequently a series of memory tests were performed which points towards a hardware failure which prevents restarting the spacecraft software successfully. This team […]

My Python port of the Plan13 algorithm is pretty much working now. I wrote a simple script to find the next pass of NOAA-17, and here is the result for finding the next pass. It outputs the time and date (in UTC), the elevation, azimuth, latitude and longitude of the point directly under the satellite, […]

Another pass of NOAA-17 this morning. A pretty nice one too, lots of good detail. Not the most noise-free image though: not sure what the regularly timed, strong interference was that comes in at the beginning, but it too seems to be synchronized at the 1hz rate, and may even be tracking the same Doppler. […]

Stanford law professor and copyright champion Lawrence Lessig came for a lunchtime lecture here at Pixar. I’ve been interested in copyright law and intellectual property rights for quite some time, and Lessig’s thoughtful writing and championing of the Creative Commons has had a significant effect in helping me formulate what I think is a nuanced […]

I’ve been toying with the idea of doing a balloon launch, perhaps carrying a full GPS and radio transmitter payload, but I think it would behoove me to get some experience attempting to find payloads that cost only a few bucks before risking hundreds of dollars. This would appear to be the answer: the Cricketsat. […]

Every once in a while, I encounter one of those odd hams who likes to homebrew his own electronics, but who views using integrated circuits as “cheating”. He’ll assure you that you can’t possibly understand how radios work if you use integrated circuits: that real homebrew radios are constructed from simple transistors. Or maybe even […]

I can never remember these formulas, so I wrote this program. I’m putting it here so I won’t lose it, and so others may benefit. #include <stdio.h> #include <stdlib.h> #include <math.h> /* $Id$ * * Written by Mark VandeWettering. * * Any copyright would be pretty stupid. Use this code as you see * fit, […]

I was trying to figure out how people really colorize satellite pictures, but wasn’t making any headway, so I just went ahead and did some relatively straightforward gimp work. I’ll write this up too, eventually. Basically it is just a set of thresholds to establish some masks (one for the ocean, one for brown land, […]