Archive for category: General

Maintenance on twitter/facebook posts for my blog…

July 10, 2011 | General | By: Mark VandeWettering

I apologize. My blog has been remarkably unsociable. Whenever I post to it, I’d like it to also post a short notice to facebook and to twitter. But recently some hiccup happened, and two posts would end up on twitter, and an annoying three would appear on facebook. I think I’ve got that sorted out. […]

Twitter Test

August 19, 2010 | General | By: Mark VandeWettering

A recent upgrade broke twitter updates on my blog. If you read this on twitter, it means that it’s working again. Addendum: Sigh. Still broken. Working on it.

Kite Photography

August 6, 2010 | General, My Projects | By: Mark VandeWettering

Tom and I took a quick break after work today to try lofting my Canon camera up in the air. We used the Picavet that Tom constructed, and ran a simple uBASIC script that just took a snapshot every five seconds. We shot a total of about 120 shots, about one fourth of which were […]

Digital piracy hits the e-book industry –

January 5, 2010 | General, Rants and Raves | By: Mark VandeWettering

Phillip Torrone pointed out a dreadful article on today: Digital piracy hits the e-book industry – A few things that I’d like to directly comment on: “With the open-source culture on the Internet, the idea of ownership — of artistic ownership — goes away,” Alexie added. “It terrifies me.” This is dreadfully annoying, […]

Gilbert Cell Mixer in LTSpice…

December 29, 2009 | General | By: Mark VandeWettering

Well, I went ahead and built the Gilbert cell mixer from the Elmer 101 pages in LTSpice. I’m not sure I understand the biasing that it uses, but it does seem to work. I’ll think about it more later.

Movie Review: Sherlock Holmes

December 27, 2009 | General | By: Mark VandeWettering

I’ve mentioned before that I’m a pretty big fan of Sherlock Holmes. Every couple of years, I dust off my copy of his stories and read them, or load them as audio books onto my iPhone and listen to them all over again. I could go on and on, but let’s just say “I’m a […]

My first attempt at the FM transponder on HO-68

December 24, 2009 | General | By: Mark VandeWettering

The new Chinese amateur radio satellite, formerly XW-1, now designated HOPE-1 or HO-68, made a pass with its FM transponder active around 10:00AM local time here. I was unable to get a signal through, no doubt in small part to some incompetence on my part, but also judging by the amount of doubling and piling […]

Actor Mickey Morton

December 16, 2009 | General | By: Mark VandeWettering

Mickey Morton had a brilliant career.   Can anyone guess why I might have stumbled across his curriculum vitae today? Hint: I’ve just watched arguably the worst two hours in television history.

Chinese Amateur Satellite XW-1 launched, beacon has been heard…

December 15, 2009 | Amateur Satellite, General | By: Mark VandeWettering

This morning, a quick check of my email and blog roll indicated that the Chinese had launched XW-1, probably the most interesting amateur satellite to launch this year (sorry SO-67).    It carries a payload with both linear and FM transponders, and it seems to have a higher orbit than current LEO satellites.    It […]

Some Document Scanner Links

December 13, 2009 | General | By: Mark VandeWettering

I love books, and I love the fact that technology is becoming increasingly easy to get books digitized and distributed online. Several years ago I got a copy of Johnson’s Natural History that I’d love to have digitized, but as yet haven’t located anyone whose willing to do it for me. But today, I found […]

Visible Storage Event @ the Computer History Museum

December 9, 2009 | General | By: Mark VandeWettering

If you haven’t visited the Computer History Museum in Mountain View, California, then this weekend might be a good time to go. On Sunday, they are having a special event celebrating their “Visible Storage” exhibit. This is a terrific exhibit which is going to be closed after December, in preparation for a new exhibit which […]

Photosynth of my office…

December 9, 2009 | General | By: Mark VandeWettering

Want to know what it is like to be me? Here is a photosynth of my office at Pixar Animation Studios. It’s my first try, combined from around 170 individual photographs. Let me know what you think. Addendum: You’ll probably need to be running Windows to view this.

Bandpass Filters

December 8, 2009 | General | By: Mark VandeWettering

Just some more playing around. I surfed to the following page, looking for bandpass filter designs, such as might be used at the input stage of a radio. Bandpass Filters. I took the 30m version of their filter, and created it in LTSpice, and did an AC analysis. As you can see, it’s not bad: […]

A Half Wave Filter in LTSpice

December 6, 2009 | General | By: Mark VandeWettering

On page 3.4 of Experimental Methods in RF Design, they have a little side bar about a particularly simple form of harmonic filter that I thought I would try to analyze in LTSpice. Here’s a screen dump of the filter I designed to operate around 7.0Mhz. It’s really pretty simple to figure out the value […]

The Christmas Season is upon us…

December 5, 2009 | General | By: Mark VandeWettering

Well, I spent the morning raking leaves in my front yard, and then went over to Target and got some new LED lights for our Christmas tree, and also got a new wreath. In keeping with our desire to decorate, I’ve changed the theme of my blog from its normal spartan whiteness to this holiday […]