Author Archive
Wednesday, September 8th, 2010
Math textbooks…on the ipad?
There is a program in California to replace 8th grade algebra textbooks with ipads. It will be interesting to see how this turns out. While I am all for trying new ways to teach a subject, singling out math as the test subject for this program seems like a bad choice. While I can understand [...]
No Comments » - Posted in Uncategorized by admin
Tuesday, July 28th, 2009
Free Math Textbooks
Came across a link for some free math texts. Link!
No Comments » - Posted in Grad School,Mathematics by admin
Friday, May 1st, 2009
Video Card Woes
The other day at work my monitors suddenly shut off. The computer was still running, which is a good sign, and connecting one of the monitors to the motherboard’s video card (and seeing an image!) quickly showed this to be a failure of my primary video card. So I harvested a video card from another [...]
No Comments » - Posted in Computers by admin
Monday, April 20th, 2009
Time Warp
So Discovery Channel is finally doing the show they should have a long time ago: a show dedicated to high speed camera footage, called “Time Warp”. I did mention a while back how amazing I find high speed camera footage. Maybe they owe me royalties for the show idea?…(or rather that video I saw in [...]
No Comments » - Posted in General Science by admin
Saturday, March 28th, 2009
An Antenna/coupler saying?
There is a joke, or saying, when it comes to designing an oscillator or amplifier: “amplifiers oscillate, and oscillators amplify” The statement describes the fact that, when attempting to design one, there are many pitfalls that cause you to have the other happen. Usually when designing an amplifier oscillations are your enemy, and you tune [...]
No Comments » - Posted in Antennas,Circuit Theory,Electromagnetics by admin
Tuesday, March 3rd, 2009
Flux Capacitors
One of my favorite things to point out to friends of mine is this fact: Remember in Back to the Future (I, II, and III) Doc Brown used a “flux capacitor” to travel through time? Well, what if I told you that every capacitor is a flux capacitor? Well that’s true. As a simple [...]
3 Comments » - Posted in Circuit Theory,Electromagnetics,Mathematics by admin
Sunday, November 23rd, 2008
Change in Comments
I need to take some time to find a good plugin and get this site setup so that spam comments are reduced — I am getting upwards of 10 spam comments a day at this point — but until then I am shutting them all off. Currently I don’t even look through the comments in [...]
No Comments » - Posted in Uncategorized by admin
Saturday, November 1st, 2008
Smith Chart Matlab function
Every now and then I write or modify a matlab function that I need for my research, and will post them to this blog here and there, with the hopes that they will be useful to someone doing antenna/microwave design. I know, there is the Matlab File Exchange (which is very useful!) , but hey, [...]
No Comments » - Posted in Antennas,Circuit Theory,Electromagnetics,Grad School,Mathematics,Matlab,Uncategorized by admin
Thursday, August 14th, 2008
HFSS Calculating incorrect Impedances…
I have been running some Ansoft HFSS simulations of infinite arrays of antennas, recently. A peculiar thing I noticed is that some of the impedance data, which is calculated from the S-parameter matrices, had sizable spikes (upwards of 300Ohms) inside a frequency band that, from the S-parameters, looked smooth and well matched. Clearly something was [...]
No Comments » - Posted in Antennas,Electromagnetics,Grad School,Mathematics by admin
Thursday, July 31st, 2008
Antenna Java Applet
Here is an interesting Java applet that allows good visualization of the fields of some basic antenna elements. http://www.falstad.com/antenna/ You can readily see the field pattern distortions that occur from things like making a dipole or loop longer than half a wavelength in size, the multiple lobes that form, and how the current distribution forms [...]