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POTA LA Historical Park : Japan and Washi Tape

 The ham radio POTA where the Rockmite was spotted in Japan! Also? The following day, the RF center conductor was secured back to the BNC jack with washi tape. Coincidence?


Los Angeles State Historical Park a few feet from the Gold Line Chinatown Station.

Getting There (Via Public Transit)

Oh my gosh! As usual, we used public transit, and it was so easy to get to the park! (I have POTA to thank for making me aware of the park. I had never seen it before even though I'd stayed within a quarter mile of it any number of times.) We took the LAX FlyAway bus from the airport to Union Station where we took the Gold Line one stop up to Chinatown. (We also took the Gold Line to our Pasadena non-radio destination.) The LAX FlyAway bus was new and very, very plush. It had leather seats and 3-prong  120 V outlets (two outlets per two seats) for charging devices. The Metro Gold Line might feel confusing if you've never taken it from Union Station before. You'll wind up on an elevated train, but to get there you head down into what feels like the bowels of the Earth to find a tunnel that will take you back up to the platform. You can get a Tap Card at a vending machine near the tunnel entrance. The day we were there, a 3 day pass was $12.

Eating Near the Park

If you want excellent Chinese food while you're in the area, we all love Yang Chow. Like just about everything else on this trip, we hadn't been there in four years. We ordered takeout food each of the three nights we were in town. 

Radio Details

The Rockmite was a bit cranky as the antenna wire eventually broke off, (see above.) The radio, embedded in the antenna, was about 6 feet up the first day, and maybe 8 feet up the second day.  

QSO/RBN spot map:

Here's the big picture. Japan!!!!

And the  more QSO-centric picture:

and then the more detailed view still. There were lots of contacts with California this time. I'm going to go out on a limb and guess it was the low antenna height, but I don't really know why.

And finally, the interactive map:

Happenings of Interest

The radio was heard in Japan!!! How? I'm  not really sure. The local ionogram doesn't offer me a lot of insight.

The closest functioning ionosonde I was able to find to the station in Japan was Guam:

Its ionosonde sheds a little light (pardon the pun since it was almost 2 in the morning in Japan) on the matter. The Guam ionosonde also observed a high MUF and a high-ish F2 Layer.

It turned out pretty handy that I washi tape my QSL cards shut. I used the same tape to wire the center conductor of the Rockmite back to the BNC jack in a pinch.

QSL Card:

RF Center Conductor:


Callsignrx RSTtx RSTTime (GMT)Frequency

Unschooling Highlights

What were we doing in LA in the first  place you might ask? The 12, 10, and 8 year old gang and I were unwinding after spending our days in Pasadena at AlienCon! The kids grew up watching the show with me gently steering them back into real science and whatnot as we enjoyed the incredible stories. This is the first time we've been able to make it since 2019. We saw talks on cryptids and giants as well as talks on where the space program is headed.


QSL rx album:


POTA (Parks on the Air)

Local Ionograms 


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