Dipole Radiation Angle

Just an on paper, (so to speak), example of how to do the F2 mapping for QSOs, (and why it's more complicated than it appears at first), today.

Let's consider this QSO to Sweden from San Francisco:

Retrieving the F2 height data immediately led me to the conclusion that the mapping app has to work in spacetime, (sadly, that's not a relativistic reference), as opposed to just in sapce. Here's the output of the Pt. Arguello ionosonde for the times around that QSO:

Notice that there is no value for hmF2 (the maximum estimated height of the F2 layer) at the actual time of the QSO. I'll need to work on statistical data selection as a result, but for now, I'm just going to go with 330 km as an estimate of what the height was at the time of the QSO.

Here's what the path along the Earth looked like

Turning on the current implementation of F2 mapping reveals we'll have lots of things to look at

But the reason I'm writing today is that skip coming from underground to go to Sweden :)

Changing the estimated F2 height makes thing better, but only a little. Clearly, the signal skipped more than once.

This post is about determining how many skips were required, and what that means for the resultant angle of radiation for our dipole antenna.

Well, since one skip isn't enough, the next thing to consider is two.

Using the midpoint method already defined in the rm-rnb-history package, I arrived at the first skip peek being located at

55.24556451189041,-110.29305571520665

Mapping that out by hacking the kml file, we wind up with the following. the lowest white line is the incoming skip with the new midpoint listed above.

In reality, the skip is about 167 miles short of its mark. Give that we're not working with laser beams, that's probably fine. Here's another look at the near miss:

I particularly enjoy that the first skip landing sight was covered in seawater, a very good ground.

Tomorrow, the actual math that I should have used. Here's a preview

Comments

The Valentine's Day Magnetic Monopole

There's an assymetry to the form of the two Maxwell's equations shown in picture 1. While the divergence of the electric field is proportional to the electric charge density at a given point, the divergence of the magnetic field is equal to zero. This is typically explained in the following way. While we know that electrons, the fundamental electric charge carriers exist, evidence seems to indicate that magnetic monopoles, the particles that would carry magnetic 'charge', either don't exist, or, the energies required to create them are so high that they are exceedingly rare. That doesn't stop us from looking for them though! Keeping with the theme of Fairbank[1] and his academic progeny over the semester break, today's post is about the discovery of a magnetic monopole candidate event by one of the Fairbank's graduate students, Blas Cabrera[2]. Cabrera was utilizing a loop type of magnetic monopole detector. Its operation is in concept very sim

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents ! Get a spiffy ebook, and fund more physics The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems , there seem to be fewer explanations of the procedure for deriving the conversion, so here goes! What do we actually want? To convert the Cartesian nabla to the nabla for another coordinate system, say… cylindrical coordinates. What we’ll need: 1. The Cartesian Nabla: 2. A set of equations relating the Cartesian coordinates to cylindrical coordinates: 3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system: How to do it: Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables. The chain

More Cowbell! Record Production using Google Forms and Charts

First, the what : This article shows how to embed a new Google Form into any web page. To demonstrate ths, a chart and form that allow blog readers to control the recording levels of each instrument in Blue Oyster Cult's "(Don't Fear) The Reaper" is used. HTML code from the Google version of the form included on this page is shown and the parts that need to be modified are highlighted. Next, the why : Google recently released an e-mail form feature that allows users of Google Documents to create an e-mail a form that automatically places each user's input into an associated spreadsheet. As it turns out, with a little bit of work, the forms that are created by Google Docs can be embedded into any web page. Now, The Goods: Click on the instrument you want turned up, click the submit button and then refresh the page. Through the magic of Google Forms as soon as you click on submit and refresh this web page, the data chart will update immediately. Turn up the:

Copasetic Flow

Search This Blog