I wonder if there's a safe way to equip people to just do simple bloodletting if they have high exposure to PFAS. I mean obviously it's better to donate, even in that case, given the steady state of most blood banks. But it's still a bit of a pain in the ass.

I believe my version is using a Knowles mic:

https://www.digikey.com/en/products/detail/syntiant/SPU0410L...

It'd imagine there's a lot of neurophysical adaptation involved as well, just like listening to a single conversation in a crowded room.

That said, hunting in an area filled with bats is probably not as effective as being in a quiet place.

Couple cool things I've learned about bats.

- They are *extremely* loud in the ultrasound range, 130db echolocation calls from something the size of a mouse.

- On an average recording, the ultrasonic range is almost exclusively filled with sound from wildlife (bugs, birds, etc). I'd expected to see lots of harmonics and whatnot from human-generated sounds but there just aren't that many. It's quiet up there.

- You can leverage these two in combination for sampling by just strapping the recording device to the roof of your car and driving around. The wind and road noise is basically absent and the echolocation calls come through loud and clear. The AudioMoth can be fitted with a GPS receiver to correlate the calls to location (and time ofc)

- There are three primary types of echolocation calls: Search - Semiregular calls just to see what's out there. Approach - Faster rate of calls once prey has been identified. Terminal - Aka feeding buzz, very high rate (200hz) of echolocation calls in the last meter or so of approach. Most of the recordings of bat calls you see on YouTube are slowed down 10x to bring the audio into listening range, but this also slows the call tempo by just as much. They make lots of calls.

- Most bat calls use frequency sweeps rather than continuous tones to pick up both distance and relative velocity of the target (akin to FMCW radar).

- There are more bats around than I realized. I started off by looking for 'good spots', but now I just set the device out on a porch. Many times you'll hear me walking up to the recording device at the end of a recording and there will be 2-3 bats overhead that I was perfectly unaware of.

- Some moths have developed jamming calls that confuse the standard echolocation calls of most bats - https://www.illinoisbats.org/echolocation-jamming-moths/ Some species of bats have developed countermeasures to that.

Bat detection/identification with ultrasonic recordings. It's been fun building the data pipeline to manage the ~30GB+ of WAV files generated every night, run through some identification processes (currently using https://github.com/rdz-oss/BattyBirdNET-Analyzer) and build a UI (mostly vibe coded lol) to help with replay, cataloging, etc.

I'm using an AudioMoth currently (https://www.openacousticdevices.info/audiomoth), am thinking about extending it to do some of the preprocessing in the field to scale things up a bit.

And of course there's nothing to say that both of these things can't be done simultaneously.

I wonder where some of this comes from. Another one is 'real unlock', it's not a common phrasing that I really recall.

https://trends.google.com/explore?q=real%2520unlock&date=all...

    •  /buddy is here for April 1st — hatch a small creature that watches you code

You really have to get your eyes adjusted to the dark to see anything with the spinthariscope. It ends up looking mostly like static on a green crt, but if your only reference frame is a cloud chamber, the volume of particles that are emitted from such a weak source is pretty remarkable.

>The reference implementation is JavaScript, whereas our pipeline is in Go. So for years we’ve been running a fleet of jsonata-js pods on Kubernetes - Node.js processes that our Go services call over RPC. That meant that for every event (and expression) we had to serialize, send over the network, evaluate, serialize the result, and finally send it back.

But either way, we're talking $25k/mo. That's not even remotely difficult to believe.

You didn't at least puff a little ack through your nostrils for that one?

I asked chatgpt to chart the number of new bullet points in the CHANGELOG.md file committed by day. I did nothing to verify accuracy, but a cursory glance doesn't disagree:

https://imgur.com/a/tky9Pkz

I just noticed this for the first time this week (it only happens to me on Instant mode).

Yuck.

Ben's vids were kind of mind-blowing for me at that time. I couldn't believe some of the control that was possible with relatively pedestrian electronics. Aaed's vids do a wonderful job of making it accessible in an applied way.

It's something I think a lot of the folks on HN would find interesting to tinker with. Nice mix of software and hardware that actually does work in physical reality. It also gives me a level of appreciation for the advances in humanoid robots that I don't think I would have had otherwise. (If you *do* get into it, I'd highly recommend getting into field oriented control with brushless motors and encoders. Small hobby servos are fun but they encapsulate a lot of the interesting parts and tend to have limited options available for things like the capstan vid linked above)