Passive infrared motion sensors
Added 2024-07-25 01:22:05 +0000 UTCHello all! I have a simpler (and sillier) video for you today:
I was hoping to have this done yesterday so I'm going to do a rapid turnaround and publish it tomorrow afternoon. I have another video that's already pretty far along (it needed experimentation which I did last week) and I'll be moving right into working on that script. It's a topic that's related to home comfort, and since I just did the awning video, I wanted to push it back and do something simple first.
This was in my ideas document and I it's been there for a long time. I wasn't super great at making sure I referenced where the idea came from back then so if any of you recommended this topic to me, I'm sorry that I forgot!
Other notes - on Friday I have something very cool getting delivered. I will let you know what that is in a video update, possibly on Friday depending on when it arrives. That will be a video topic of course, but it'll be a while before I pursue making it.
And the Q&A video on Aztec, plus sights and sounds, is going to take priority once I have some sense of how the next video is going along. The first few days of August are going to pull me away from the office so I'm trying to get a lot done before that happens.
Last order of business, the livestream rig has had zero progress! Hooray! I've done a teeny tiny bit of looking into what I need to get to make that happen but a jumble of ideas is buzzing around my head in a way that rarely happens so I've back-burnered that for now. You'll probably just get a surprise post about a live stream test at some point :)
Okay, well, toodles! And thanks so much for being here.
Comments
All this talk about balance & imbalance makes me think these things are actually measuring The FORCE!
Markintosh
2024-07-25 20:59:19 +0000 UTCUltrasonic motion sensors which use Doppler shift are also quite interesting, although they're used a lot less in security now because passive infrared is so much cheaper
Mark Lefler
2024-07-25 17:40:31 +0000 UTCInteresting, I never thought about these... Thank you very much!
MrHammond
2024-07-25 17:39:48 +0000 UTCEarlier on this very day, I was listening to Adam Felber on a podcast talking about when he was young, he worked in an home security/alarm company. He had plenty of time on his hands, and figured out how to defeat motion detectors in the store by using gloves and a big piece of cardboard. Your video comes out explaining how these sensors work which explains how he was able to avoid tripping the detectors.
David Weintraub
2024-07-25 17:08:26 +0000 UTCFWIW, the AT&T Merlin PBX at my 1st job decades ago had the Jimmy Fontanez as hold music, and ages ago, I searched for it on YouTube and your channel came up. So that's the weird roundabout way I got here.
Crash Cash
2024-07-25 16:58:58 +0000 UTC"With a Dremel tool and a cut-off wheel, *everything* takes a flat-blade screwdriver."
Crash Cash
2024-07-25 16:15:15 +0000 UTCRe: Patreon. You're welcome, and you're worth it!
Kevin Tessner
2024-07-25 13:35:46 +0000 UTCFor 3 seconds I thought I was gonna be able to make a PBS joke in the comments and you beat me to it. Seems I've never had an original thought in my life
Sara Urban
2024-07-25 05:16:55 +0000 UTCI don't remember, but do you have a thermal camera? You could try using that to look through the lens.
Dennis Henderson
2024-07-25 05:11:08 +0000 UTCThanks, Alec for another great video! Clive (the big, live one) also has a good explanation. I'm sure you already watched it as part of your research, but others might be interested. https://www.youtube.com/watch?v=evZM2_RTvTU&t=50s
Eric Nelson
2024-07-25 04:10:04 +0000 UTCYou can defeat these sensors by either moving very slowly or using something like cardboard which has a similar temperature to the background to block your body infrared. The detector electronics is generally a simple bandpass filter, so it's looking for rhythmic flashes of a certain frequency.
Mark Lefler
2024-07-25 03:07:00 +0000 UTCPossible future closing line? "This... is Technology Connections" 😅
Linh Pham
2024-07-25 02:51:09 +0000 UTCI always assumed there was a different sensor for each lens segment. Thanks!
Dan Oberste
2024-07-25 02:26:38 +0000 UTCI don't have it with me to look at now but there was a fairly complicated IC on the board. I'll try to remember to follow-up tomorrow and see if there's a datasheet. This was one of those topics where I had already researched this long ago and I mostly just barfed out a script which I fact-checked and filled in as I asked questions. I call it my slow-ball game, though maybe bottle episode is better :)
Technology Connections
2024-07-25 02:25:43 +0000 UTCI was thinking a little about how you were struggling to demonstrate the effect and it made me think back to these special light boxes we used in high school which only produced thin beams of light, aimed at prisms, when we were learning about how light works... Maybe something like that with a piece of paper behind the lens to catch the light that's gone through? :o
Kris Asick
2024-07-25 02:23:29 +0000 UTCMost of them are really simple, just a FET in the sensor package and 3 external ICs, an opamp, timer and comparator, although the modern single custom IC solutions could be doing some counting, but most data sheets for them are in Chinese. I have a couple videos about PIR sensor teardowns that kinda talk about some of it briefly, I assume you found them during your research? When I saw the notification I thought for sure you would have used my hi-res de-lid photo on Wikipedia commons but you did one better and took one apart yourself.
WizardTim
2024-07-25 02:21:02 +0000 UTCWhat a treat to get so many videos lately! I’ve always wondered how these worked so thank you
Eli Maxwell
2024-07-25 02:16:14 +0000 UTCVery enlightening! Loved the looping joke.
Jeremy Vanderburg
2024-07-25 02:12:44 +0000 UTCHeh, well to be honest I have no idea what's actually going on in the logic. I didn't mean to imply I did, though I can see in hindsight it definitely sounds like I do.
Technology Connections
2024-07-25 02:06:09 +0000 UTCExciting!
eaglebeagle
2024-07-25 02:00:25 +0000 UTCInteresting yours counts blips for distance, all the ones I've looked at just compare the sensor signal amplitude to the potentiometer signal.
WizardTim
2024-07-25 01:54:43 +0000 UTCYou always ruin the magic!! 🤣
AArexx AAron Ruscetta
2024-07-25 01:42:34 +0000 UTCFor live streaming you might want to look at the Osee GoStream. It’s pretty amazing for the price, and I’m coming from broadcast level production space so not easily impressed, though I bought one myself under the wife radar. They are on sale now and you might even be able to swing a sponsored one?
The Griffiths Family
2024-07-25 01:34:18 +0000 UTCYou're my favorite notification, Alec.
Matheus Bitencourt
2024-07-25 01:26:02 +0000 UTC
