Skip to main content

More Propagation Signal Strength vs. Tide Data at US-0757 vs Project TouCans' Vertical on 20 meters

 In radio engineering as in all thing, it pays to be kind. This morning while activating US-0757 with TouCans Vertical, I noticed a swimmer I'd seen before headed towards the pier I was prerched on. 

Bear with me a little nautical explanation is in order to understand the rest of the this tale, so here goes. 

There are currents in the San Francisco Bay. Currents thtat sweep out towards the ocean are called ebb currents. Currents that see in from the ocean are called flood currents. Even at Hyde St. PIer in its somewhat sheltered indentation in the shore of the Bay, swimmers experience these currents. They're a thing and sometimes they're just about as fast as a swimmer cares to swim.

Getting back to this morning, the swimmer I saw coming occaionally takes advantage of currents to do 'infinite lap pool' swimming under the pier. She backstrokes while going nowhere because she adjusts her speed to the speed of the current. She also sings quite pleasantly while doing all this.

Anyway, I saw her headed towards the pier I was seated on and immediately pulled up the ground wire for Project TouCans that had been suspended in the Bay water below till just then. And. AND! And? 

The receive signal got so much better! The interfering AM broadcast station went away all toghether. Some of the noise from the power supply went away. But wait! There's more! The transmit signal, (as exhibited by the Reverse Beacon Network stayed the same! It even got a bit stronger over time as the POTA carried on!

I don't know what the mechanism is that caused this, but I'm loving it! I activate the park in just under an hour. It turns out the vertical antenna only takes about 10 minutes to set up at a location I'm already familiar with.

Here's the QSO map for the activation


No QSOs to Alaska today, but the rig was spotted in Hawaii just before I had to leave for the rest of the day.

Here's the QSO list

Callsigntx RSTrx RSTTime (GMT)Frequency
kg6oki4495592024/11/04 15:15:0014057.4
ve7vak3395592024/11/04 15:19:0014057.4
ad0wb5595592024/11/04 15:23:0014057.4
n6gc5695992024/11/04 15:30:0014057.4
kq6qb495592024/11/04 15:34:0014057.4
k7evm3395592024/11/04 15:36:0014057.4
k6hwd3395992024/11/04 15:39:0014057.4
k7tmm5595992024/11/04 15:41:0014057.4
k7sps3395992024/11/04 15:45:0014057.4
w6zkh3395592024/11/04 15:48:0014057.4
kc7wxd3395992024/11/04 15:50:0014057.4
n6ilj3395292024/11/04 15:54:0014057.4

And finally, here's the animated Cesium map of the QSOs. I haven't done one of these in a while. The F2 data are not accurate, but everything else is. Rewind the time slider to the start to see all the QSOs and spots at once. Click on play to see them over time. (Notice that the Hawaii spot happens at about Hawaii grey line.) Click on any signal path to see specific information like call sign, time, and signal strength.



Here's the data for Reverse Beacon Spotting station SNR with respect to tide levels in the Bay












Comments

Popular posts from this blog

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: