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Altmode
Personal blog · altmode.orgsecurityhardware
Altmode is a personal blog at altmode.org about security and hardware. Since 2015, 3 different Hacker News readers have linked it 3 times. It is still writing: the last post was on 2026-09-09, and you can follow it by feed.
Too few sampled comments (2) to say how often HN recommends it.?
Why HN links it
HN commenters link this blog's posts on ultrasonic beacons hidden in ads, including an experiment searching for them in Cartoon Network audio. The comments discuss the topic and cite the post without judging the writing.
Summarised by Claude from a sample of 2 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Another word for escape
Most-linked posts?
- /2015/11/13/searching-for-ultrasonic-beacons/2 people · 2 mentions · first linked 2015-11-13
What Hacker News says?
Inaudible is a fuzzy line. I remember growing up always hearing around the house the hum of the CRT TV when my parents would turn the cablebox off and not realize they left the tv running. Parents never heard anything. You start to lose hearing at upper frequencies around as early as in your 30's... when I talk to my friends about this, a surprising number of them (even the non-techies) remember this barely-audible-…
Comment linking /2015/11/13/searching-for-ultrasonic-beacons/
on “Beware of ads that use inaudible sound to link your phone, TV, tablet, and PC”Submitted Passwords: what minimum length? as a story · 1 points
HN discussion@jimfenton recorded some audio from Cartoon Network in an attempt to find these beacons: http://altmode.org/2015/11/13/searching-for-ultrasonic-beaco... FSK at 17.5 and 18.5 kHZ is one possibility, but wasn't detected in this experiment.
Comment linking /2015/11/13/searching-for-ultrasonic-beacons/
on “Beware of ads that use inaudible sound to link your phone, TV, tablet, and PC”