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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












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