1. Putting Faraday shielding fabric to the test.

    25 November 2020

    Last year at Thotcon the presenters were given what were purported to be faraday shielded backpacks - backpacks manufactured with fabric woven out of very fine conductive wires that are said to reflect radio frequency signals inside and outside.  The idea is that if you have a cellphone and you put it inside the bag, you could be sure that the phone was not talking to any cell towers so it would be harder to track the person carrying the phone, as well as preventing any malware that may have been installed from phoning home.  So the reasoning goes, even if …

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  2. Neologism: Cigarette principle

    17 November 2020

    cigarette principle - noun phrase - The phenomenon in which, if you want something to happen sooner, you should do something that will immediately inconvenience you during the act of that something occurring.  Comes originally from the act of making a public transit bus arrive faster by lighting up a cigarette, which would of course cause you to ditch the smoke, dig out your bus pass or change, board and pay for the ride.  Generalizes effectively.

    h/t: Mom

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  3. Embedded environment monitoring.

    02 November 2020

    Disclaimer: This post has lots of links to the Adafruit website.  There are no referral links, I received no consideration, I just buy parts from there and do cool things with them.

    A couple of ~~~weeks~~~ months ago I did a writeup of a prototype environment monitoring device for my office built out of a Raspberry Pi Zero W and some off the shelf components.  In the time since I've found time here and there to work on the embedded version, which doesn't use a full computer system but a microcontroller with just enough functionality to drive a couple of …

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  4. Setting up a mail relay server with Postfix, DKIM, and a little Nebula trickery.

    23 October 2020

    Given the proliferation of spam on just about every vaguely workable platform these days it seems sheer insanity to attempt to run your own mail server.  If it's out there, it's ripe for abuse in one way in another.  And yet, e-mail is still probably one of the best ways to get status reports from your machines every day (my SMTP bridge notwithstanding).  It is thus that the default configuration for mail servers these days defaults to "no way in hell will I relay a message for you," which is a net good for the the Internet as a whole …

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  5. Wrestling with mental and physical health.

    06 October 2020

    This isn't easy for me to write because it involves my mental health.  So, if it's not your bag feel free to skip this post.

    Helping my mom since her cancer diagnosis has left me in this peculiar state where I don't actually know what I'm feeling.  I call it "running on wires," as in, the silicon I'm connected to is running me, and the organics are off doing... something, maybe.  My therapist calls it alexithymia, and reading about it that's as good a word for it as any.

    I've been fighting with clinical depression for most of my life …

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  6. Calculating entropy with Python.

    29 September 2020

    Fun fact: There is more than one kind of entropy out there.

    If you've been through high school chemistry or physics, you might have learned about thermodynamic entropy, which is (roughly speaking) the amount of disorder in a closed system.  Alternatively, and a little more precisely, thermodynamic entropy can be defined as the heat in a volume of space equalizing throughout the volume.  But that's not the kind of entropy that I'm talking about.

    Information theory has its own concept of entropy.  One way of explaining information theory is that it's the mathematical study of messages as they travel through …

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  7. Chemotherapy begins.

    15 September 2020

    Mom had her first round of chemotherapy last Tuesday.  Early that morning I drove her to the Hillman Cancer Center at UPMC, got her checked in, and had to leave as they took her back because, due to the pandemic and generally immunosuppressed state of the other patients in the office I posed a contamination risk.  I spent most of the day puttering around the house, fixing stuff up, cleaning, and getting a bit of dayjob work done after dropping her off.  Mom spent most of the day hooked up to one IV line or another.  Unsurprisingly, it took some …

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