Shallow Thoughts

Monitoring Heart Rate with a PineTime Smartwatch

I've been wanting a heart rate monitor I can check while exercising.

I've tried carrying a pulse oximeter, but while they work fine for resting pulse sitting at home, they seem utterly incapable of measuring a raised pulse outdoors on the trail. (Too bad, since it would be nice to have the oxygen reading when hiking up a mountain at 10,000 feet.) I wonder if they have that problem for everybody; it may have to do with my very small fingers.

There's the chest band option, from brands like Polar. But I tried a Polar HRM years ago and found it exceedingly uncomfortable. I don't deal well with a tight band under my breasts, especially while exercising.

I've wondered about smart watches. Some people say they work fine for monitoring pulse rate, others say they're not so good. But Dave tried a couple of smart watches a year or two back, and I saw what he went through trying to get it working. It's probably all painless if you don't mind being part of the Apple or Samsung ecosystem, using devices and software exclusively from one company and having all your data uploaded to that company's cloud (there to be shared or leaked or whatever). But that's not really my thing.

Then I read about the PineTime watch.

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Tags: health, android, open source
[ 13:42 Sep 28, 2026    More tech | permalink to this entry | ]

Debian's American Sorting

I was writing a little example of a GTK treeview for my scripts repository when I noticed something rather funny about Debian's dictionaries.

My example uses /usr/share/dict/words as a handy source of data, just A through C since it turns out the TreeStore is rather slow in adding data. I expected top-level items of A, B, and C. What I got instead was: A, B, C, É, C, É, C, É, C.

What I got when I expanded the categories was even weirder: a bunch of éclairs mixed in with all my C words.

Was there something weird about my script? It didn't seem likely: I wasn't doing any sorting, just reading lines one by one from the file.

Sure enough, looking at /usr/share/dict/words confirmed what I was seeing:

laims
Clair
éclair
Claire
Claire's
Clairol
Clairol's
Clair's
éclair's
éclairs
clairvoyance
clairvoyance's
clairvoyant

and several similar sections later on.

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Tags: linux, debian
[ 11:44 Sep 13, 2026    More linux | permalink to this entry | ]

The Fluorescent Back Yard

And, a scorpion!

Some years ago, I bought a long wave 365nm UV flashlight through a group purchase the local geology club made.

I had a few UV flashlights, cheap "scorpion lights" you see at gift shops. But it turns out the cheap lights don't really show the fluorescent colors of most rocks very well; this one was recommended by an expert in the geology club as a low-cost entry to seeing fluorescent rock colors. (They told us you can see even more with more expensive lights — with a warning not to get the 6-Watt UV-Tools light, as its performance is very disappointing -- but I went for the entry-level option.)

I used it a few times, marveled at the cool colors, and then put it away. Recently I dug it out again and went walking around the yard after dark.

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Tags: science, geology, nature, scorpion, uv
[ 12:35 Aug 16, 2026    More nature | permalink to this entry | ]

Wall Snake

When they installed the mini-split heat pump in the bedroom (and this year was the year to do it! it's been a lifesaver this month!) the installers drilled a hole in the wrong place. One of them noticed my crochet kingsnake in the living room and suggested that rather than filling the hole normally, I could crochet a snake to put in the hole. I loved the idea and told him not to fill the hole.

It took a few tries: I thought the hole was bigger than it actually was, and I didn't drag a ladder upstairs to the bedroom until after I was half done with the snake, at which point I discovered my snake was too big and I'd have to pull it apart and start over with a smaller snake. But I'm happy with the result.

Tags: crochet, maker
[ 10:59 Aug 10, 2026    More art | permalink to this entry | ]

How Many Photos Have I Taken?

I was visiting relatives, and we were looking through some photos when someone asked me, "How many photos do you have, anyway?"

I had never thought about it. But I have a Linux laptop with all my digital photos on it, so it shouldn't be too hard to answer that at least for the digital ones. (I'm not going to go count the slides in the albums on the closet shelf.)

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Tags: linux, cmdline
[ 14:11 Aug 07, 2026    More linux/cmdline | permalink to this entry | ]

A Linux-Based Video Player Appliance

Our MP4 player box died. It was a little cheapo device that reads video files (mostly ripped from CD) off an SD card or flash drive, then plays them on the TV over HDMI.

We've had a couple of them, and they're not great: the user interface is terrible, the playback is sometimes laggy and doesn't always have good audio/video sync. But they're cheap, they do play videos, more or less, and they're easy to drive from an infrared remote. On the other hand, I've also read about how this sort of device is often riddled with malware. That's maybe not a huge risk because we don't give them access to our network, but still, it seems like a bad idea.

"Let's use a #RaspberryPi as our media center", I said. "It'll be so much better than those cheap MP4 players. And I'm sure there are options for training an IR remote, or maybe a way to use a phone as a remote." Little did I know what I was getting into.

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Tags: linux, video, programming, php, web
[ 15:46 Jul 12, 2026    More linux | permalink to this entry | ]

Overriding Emacs' Broken Bookmark Position Code (Updated)

(Note: I've updated this post: see the solution at the end.)

Emacs has a useful function called bookmarks, where you can make short names for files you visit often.

But bookmarks has one terrible misfeature: it also remembers your position in the file.

That sounds like a good thing, right? But the problem is that the bookmarks system only records these positions sporadically. So it's easy to get stuck on a position you were editing months ago.

For example: I have a bookmark for the file where I keep track of appointments and other calendar entries. But lately, every time I open this bookmark, it opens it with the cursor positioned on September 24. That's three months away; its not the part of the file I'm interested in right now.

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Tags: emacs, editors
[ 13:09 Jun 28, 2026    More linux/editors | permalink to this entry | ]

Full Self Driving

They're doing roadwork on the highway near the house.

This is the sort of paving where they melt the old pavement, chew it all up into little pieces, mix it with tar or something then smear it back on the road.

They do it all at one time: there's a procession of trucks that each does a different step, and they all move together at a slow walking pace.

We rode our bikes over to watch it happening, and we noticed something interesting.

There's no one driving any of the trucks! They all have a cab, but the driver's seat is empty.

There's a person walking alongside the lead truck. He isn't holding any obvious control mechanism, though.

I never knew that road paving was an application where they're already using "full self driving".

Tags: roadwork
[ 13:34 Jun 21, 2026    More misc | permalink to this entry | ]