Switching diodes and rectifying diodes

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I had an envelope full of SMD diodes arrive today. Three different types in three different sizes, so nine bundles. Unlabeled!

I’m not sure what they were thinking at the shop. I got them from here.

I managed to figure out that the ones marked ‘S4’ were the Schottky diodes (1N5819WS). I think the ones labeled ‘T4’ are the switching diodes (1N4148WS) and the ones labeled ‘T7’ and ‘A7’ are the rectifying diodes (1N4007), but I’m not sure of that yet.

I asked ChatGPT for help and it explained how I can devise a test circuit, so that’s on my TODO list for tomorrow.

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:

Unboxing #5: Unboxing of AliExpress TE-801 Third Hand With Magnifier | In The Lab With Jay Jay

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This post is part of my video blog and you can find more information about this video on this show’s homepage which is here.

You can support this channel on Patreon: patreon.com/JohnElliotV

In this video I unbox two “different” helping hands (AKA “third hand”) only to discover they are the same TE-801 model.

I purchased these separately on AliExpress:

They are exactly the same product so if you’re planning to purchase might as well get the cheapest option. Note that the first link above also has a separate more expensive option which is actually a different product, I didn’t get one of those.

In addition to unboxing these third hands I also add some 4mm heat shrink to the alligator clips to take the bite out of the teeth.

Note: in this video I have the annoying habit of calling “heat shrink”, “shrink wrap”. The correct term is heat shrink, shrink wrap is a different type of thing.

In the video I use 4mm yellow heat shrink:

The hot air gun I use is a part of my Horusdy Soldering Station.

The batteries I use are Duracell AAA batteries.

My gloves are:

Thanks very much for watching! And please remember to hit like and subscribe!

Following is a product I use picked at random from my collection which may appear in my videos. Clicking through on this to find and click on the green affiliate links before purchasing from eBay or AliExpress is a great way to support the channel at no cost to you. Thanks!

ENGINEER PA-09 Crimping ToolThis is an image of the product.notes

Let’s go shopping!

UV light

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Got myself a USB powered UV light. It came with a few tubes of solder mask:

I’m gonna keep this in my booth where it will be used. Don’t want to use it anywhere near where I keep my UV solder mask because I don’t want to accidentally cure it!
John's UV light, switched off
John's UV light, switched on