G3ZJO just posted a nice little blog entry about the use of LEDs (which are nearly ubiquitous) as varicaps (which are often harder to find). Lots of people are using these in their QRSS beacons, no doubt in part to the work of Hans Summer which was the first person to bring them to my [...]
Archive for month: April, 2010
Here is a nifty little page that I haven’t had time to absorb, but it gives some good strategy hints on playing Connect Four. Saved for later perusal. Connect-4.
I’ve been wanting to put a ham radio into my car for quite some time. The obvious thing would have been to get a nice 2m/70cm dual bander, but I didn’t really want to invest a huge chunk of change into it at this time, so I decided to go with a simple basic 2m [...]
I’ve been interested in techniques where amateurs can digitize images and models for quite a bit. This website percolated to the top during today’s relaxing web browsing: it’s pretty spiffy, and is interesting on a couple of fronts, not the least of which is that the author designed the gearbox for tracking a laser using [...]
The game Connect Four is a pretty neat little game, which was solved back in 1988 by two different individuals: James Allen and Victor Allis. It makes a pretty nifty benchmark too, called Fhourstones. My modern desktop evaluates over 10 million positions per second, and can solve the entire game in about 3 minutes. Pretty [...]
A couple of years ago, I mused about an “easy” checkers problem which my checkers program Milhouse found to be pretty difficult. Here’s the position again, with White to move and win: (I didn’t mention the source of the puzzle before, I got it out of one of Rob Pike’s books, not sure which one. [...]
While mucking around this morning, I bumped across the Sixty Symbols website, something I hadn’t seen before. It describes itself thusly: Ever been confused by all the letters and squiggles used by scientists? Hopefully this site will unravel some of those mysteries. Sixty Symbols is a collection of videos about physics and astronomy presented by [...]
Yesterday I was in our Atrium, and Craig had his iPad with him. I got into a discussion with him and Loren about why I thought the device was very cool. (I also told them why I had been actively discouraged from becoming an iPhone developer earlier, but that’s a story for a different time.) [...]
I sent a copy of this as a letter to Joel Johnson @ Gizmodo. I have no pre-existing relationship with Joel, but was dismayed by their treatment of the next-generation iPhone release, and thought to express some of the reasons behind my general displeasure. Hey Joel… I thought I might drop you this little missive [...]
G4ILO had much better success than me with similar equipment. His mp3′s are way more convincing than mine. G4ILO’s Blog: Arecibo success.
Or should that be maybe? Arecibo? In the world of visual astronomy, it is well known that your eye’s peak sensitivity to light doesn’t occur right when you are staring at an object directly. To detect the faintest galaxies, you must stare slightly away from where the object is, and you’ll see it pop into [...]
Sigh. Not hearing anything from the Moon. Tuning into the live ustream.tv video/chat line it appears that lots of people with much larger/better setups than me are also having difficulty hearing anything, so I am not the only one. Given that under the best of circumstances, my unproven antenna would have barely enough gain, I [...]
So, my barely finished antenna got just one basic operational test last night. I monitored the pass of SEEDS II, which was squawking in Digitalker mode on 437.485, which is somewhat higher than the nominal frequency this thing is tuned for (it’s centered for operation around 432). I haven’t really tried SEEDS II in a [...]
Will I hear anything from the moon tomorrow? Your guess is as good as mine.
Apparently the Arecibo dish will be streaming video from their location during the Moonbounce event over the next few days. Check out the following link, or the embedded video stream: KP4AO EME on USTREAM: Earth-Moon-Earth EmE transmissions from the Arecibo Observatory, the worlds largest radio telescope.. Science. Free TV : Ustream