The town of Windham, New Hampshire, became the site of a controversy when the results of a ballot recount by hand didn’t match the original results. This has some interesting implications for ballot scanning and errors in the process, so I think it’s fair game for this blog. I’ll have to get into the politics to give it context, though.
The four winning candidates for the state legislature were found to have gotten about 300 additional votes each, while the one who requested the recount got fewer, so the results weren’t affected. Still, it was appropriate to ask why the scanners’ total was so far off. The town accordingly had an audit conducted.
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One of my favorite areas in Berlin is the Museum Island. It includes the Egyptian Museum, which is part of the Neues Museum. Among its most famous possessions is a bust of Nefertiti which dates from about 1340 BCE. The museum has an entire room dedicated to Nefertiti. 
Mad File Format Science 
How broadcast FM can wreck your receiving system
Today I came upon some news weird enough to justify a post on this long-dormant blog. Ars Technica reports that it “began on January 30 and afflicted Mazdas from model years 2014 to 2017 when the cars were tuned to the local NPR station, KUOW 94.9. At some point during the day’s broadcast, a signal from KUOW caused the Mazdas’ infotainment systems to crash—the screens died and the radios were stuck on 94.9 FM.”
That shouldn’t be possible, right? A broadcast FM signal is just frequency-modulated audio. It might deafen you or damage the speakers, but it shouldn’t make the receiver stop working! Well, actually, it isn’t just audio. Broadcasters can optionally use the Radio Broadcast Data System (RBDS), which supports encoded digital data. It uses a 57 kHz subcarrier, well above the limits of human hearing. The data is encoded at 1187.5 bits per second, a strange-sounding number that yields 48 cycles of the subcarrier for every bit. Error correction codes bring the effective data rate down to 730 bits per second.
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Posted in commentary, News
Tagged radio, software