Category Archives: Learning

The Problems of Philosophy, further reading

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At the end of The Problems of Philosophy, Bertrand Russell says:

The student who wishes to acquire an elementary knowledge of
philosophy will find it both easier and more profitable to read some
of the works of the great philosophers than to attempt to derive an
all-round view from handbooks. The following are specially
recommended:

AliExpress diodes

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I ordered a bunch of SMD diodes from AliExpress (nine different types), and nine packages arrived, but they weren’t labeled. I tested everything to infer what I got, and they didn’t ship me what I ordered. My notes are here and the video of me doing all this is here.

I kept a note of the seller and will try to not order from them again. In the mean time I think I have filed the components that did arrive in the correct drawer.

Below are two happy snaps from this project. I guess on the bright side I got some practice doing SMD soldering and using my signal generator and my scope.

Oh, and I added a new item to my debugging notes, viz “is it plugged into the right socket?” (I had my output cable on the signal generator plugged into the wrong BNC connector on the device, that took some figuring out…)

John's test rig

John's test rig, labeled

Mail log IP address count

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The following monster will parse the mail log and report on unique host connections along with a count.

cat /var/log/mail.log | \
  grep ' connect from unknown' | \
  awk '{ print $8 }' | \
  sort | \
  sed -n 's/.*\[\([0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\)\].*/\1/p' | \
  awk '{count[$1]++} END {for (word in count) print count[word], word}' | \
  sort -n

Data formats including YAML

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I finally got around to reading about YAML at Wikipedia. Worth doing if you use YAML anywhere and haven’t read the YAML page yet.

The Wikipedia article links to the official website: yaml.org, which is good fun. It’s written in YAML! :D

If you’re interested in data formats and markup languages here’s some other reading on the subject:

In The Lab With Jay Jay – September 6, 2023 – Enameled Bodge Wire With UV Solder Mask

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This post is part of my video blog: In The Lab With Jay Jay.

In this video I solder three different sized bodge wires onto some perfboard for practice and for the purpose of exposition. After attaching the three bodge wires I cover them with UV solder mask.

If you haven’t heard of the expression “bodge wire” before, ChatGPT will explain.

I want to thank my mate Bruce from Branchus Creations for recommending the enameled wire of various sizes, the Swann Morton blades, and the Amtech flux.

I got three rolls of this enameled copper wire from AliExpress:

The diameters of the various rolls I got were:

Size mm inches
Small 0.07mm 0.003″
Medium 0.16mm 0.006″
Large 0.31mm 0.012″

I got the “coppery” colour, not the red stuff.

The Swann Morton blade handles I got were these:

I got three types of blades in #15C, #15, and #10 sizes:

The #15C Swann Morton blade is the smallest and is so far my favourite. The #15C is the blade I use in this video.

My flux is:

The industrial/precision tweezers I mention in the video are these:

The solder lugs I refer to are these:

The perfboard I used in this video was a 2x8cm board which I picked up from AliExpress:

I use two microscopes in this video:

In the video I reference my thermal imager:

My gloves are:

My head-mounted magnifying glasses are:

The soldering iron I use in this video is a part of my Horusdy soldering station:

My desoldering pump came in this kit:

The solder mask I ordered was this green stuff, but the stuff they actually sent me was red:

The solder I use in this video is:

My paint brush is the 5/0 sized brush from this set:

The blow torch I mention in this video is this one:

My Kapton tape and tape dispenser are these:

The bench multimeter I use in the video is a:

  • OWON XDM1041 Bench Multimeter

The isopropyl (IPA) alcohol I use in this video is this stuff: