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Today I Learned: Reverse Beacon Sometimes Truncates Callsigns

 This is kinda interesting, and gives me a bit more faith as well as a bit more data in and about the Rockmite. (Funny how those two things—faith and data—often go hand in hand.) The Reverse Beacon Network, (RBN), uses software to decode Morse code. The software is quite good, but today I found out it's not perfect. While working on my own python script for reading the telnet data stream that feeds the RBN site directly, I typed in a search string for my callsign—KD0FNR—as KD0*. Then, I tried doing the same thing on the RBN web site. The results I got back were unexpected, but answered a lot of questions.

RBN map showing KD0F* QSOs

Callsigns that were variants of mine like KD0F, KD0FN and KD0FX were returrned. A lot of them appear to actually be my callsign misinterpreted by the software Morse code decoder, and tell a story of the radio's operations that fill in the gaps I've been wondering about up until now.

KD0FN is almost certainly me since a review of the FCC database reveals that callsign is no longer active. KD0FX? Also me in almost all certainty. if you leave off the last dit of KD0FNR it translates to KD0FX.

To further pare down the results, I also sorted by the frequency of the spotted stations. The Reverse Beacon Network has only spotted the Rockmite's full callsign—KD0FNR—on the following 4 frequencies over the last few months:


Given a method to look at these other callsigns, what can we find out?

Why doesn't CA hear me on ground wave?

Apparently they do on occasion,


when it's about 4 in the morning here in San Francisco; when the ionosphere is completely shut down. About exactly when you'd expect groundwave propagation to be detectable.

But, is KD0F someone else? It doesn't seem likely. A search on the specific call sign reveals activity that only lines up on the limited set of frequencies the Rockmite 20 supports.

The rockmite occasionally hits Hawaii, why not further East?

Again, the answer is that well, occasionally it probably does. Looking back a few months, we once again see KD0F, but this time the station was spotted in North Carolina. 


The timing fits, and once again it's on one of the Rockmite's frequencies.The timing in fact fits remarkably well as it occurred at 16:46 PST which is the same half hour during which the Rockmite reaches Hawaii.


Takeaway:

I need to log my radio operation activities more completely to provide an additional check for reseults like the ones shown above, but the radio is doing more than I thought it was. It's operating in a manner that actually makes sense.

Anyway:

There's also really cool stuff to be done here using a github screen scraping as outlined by Simon Willison's example of mapping PG&E outages over time. Similar things would help to analyze how the radio is working.



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