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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The curse of HTML mail
It’s been most of a year since I last posted here, but I wanted to rant about HTML mail, and this is the right blog for it. People complain about the intrusiveness of Web tracking, but email tracking is even worse. I’ve noticed this especially after subscribing to a couple of Substack newsletters. They’re sent as HTML, and whenever possible, I click the link to the equivalent Web page, which is less intrusive. Every link in a Substack newsletter is a tracking link, with the odd exception of the link to the Substack page.
The links in a Substack newsletter don’t go to the target page but to a Substack redirection URL. Their purpose is to let Substack know about everything you click on. There are no terms or privacy policy in the email telling you what Substack uses the information for.
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Tagged email, HTML