#78 See thru walls! Microwave Movement Sensor

[@aspectcarl]

from the application note :) On and off switching of certain devices (relay, LED, motor, etc.) may generated high magnitude of transient noise at the IF terminal. Careful PCB layout and time masking is necessary to prevent false triggering. compare the shielding and via stitching on the transceiver vs your signal amplifier which is probably boosting everything including 50hz. You need to revisit your amplifier, move to twisted pair for your signal and consider placing your amplifier on a beefy groundplane, a braid between the transceiver ground plane and the amplifier ground plane should help with noise rejection. consider retesting with amplifier powered by a battery :)

[@RalphBacon]

You're spot on there Carl. As soon as I saw the 50Hz signal appear on the HB100's output I guessed what was going on. I've had problems in the past powering the Arduino (and associated add-ons) from the USB hub, it's not the cleanest 5v supply either. I might just try and clean up the circuitry before dismantling it in despair! Thanks for the info, if I ever get it working reliably I'll let everyone know.

[@4DRC_]

The lm2907 frequency to voltage converter is another good option for data processing if you would rather work in analog voltage than frequency.

[@RalphBacon]

Indeed, an excellent point you raise there ElectricAvian, thanks for posting.

[@GaryMcKinnonUFO]

There's a nice one now, an RFL something or other, also using Doppler.

[@RalphBacon]

Not helping, Gary 😁 Where is the link? And price? C'mon, we're all waiting!

[@grahamwise5719]

The HB100 is wide beam pattern, just what you need for automatic opening doors. A radar gun to measure cars etc, need a directional antenna so you can pick one car not a group. I have a lamp with the XYC-WB-DC and can't hide behide a brick wall it still detects you, unlike a PIR.

[@RalphBacon]

Brilliant, thanks for confirming that there is no place to hide with one of these, Graham. And for the information regarding the beam pattern, who knew? Well, you did, obviously but not many I suspect, so thanks for sharing, great to hear from you.

[@willofirony]

Excellent video, Ralph. I suspect that the HB100 would be of more use to robot constructors than it would to those concerned with security applications. The accurate distance detection and approach speed possibilities are intriguing. Well done on finding a device that is truly Arduino compatible device. Another application might be to discover just how and when a ball of string always manages to get ravelled .around every gadget in that oddments drawer in one's kitchen. However, one would probably be forced to conclude that the string is simply obeying the 3rd law of thermodynamics.

[@RalphBacon]

Actually, Michael, the ball of string issue has nothing to do with thermodynamics, it's far simpler than that. A ball of string (in a drawer, for example) obeys the oft-forgotten faerie-law which states that "a ball of string at rest attracts string fairies, the number of which is proportional to the size of the ball. The same applies to kittens". Unfortunately, even a microwave sensor does not detect faerie movement as they do not block or reflect microwaves, but you probably know that already. It will detect kittens, however. Thanks for posting!

[@thomasvnl]

Thanks Ralph. I ordered a few of these modules right away (the XYC-WB-DC anyway) for presence detection. Hopefully I can get them to not detect the neighbours but only the presence in my own home :')

[@RalphBacon]

Well, Thomas, you never know until you try. But mounting this in a sealed, waterproof box and still have it reliably detect movement could be its selling point. Or perhaps the trees moving in the wind is enough to drive your neighbours mad as your garden floodlight turns on for the umpteenth time that evening! Let us know how you get on, right? Thanks for posting.

[@thomasvnl]

Ralph S Bacon I wasn't planning on using it outside. I wanted to use it to detect if there are people inside my house (combining this data with other data like WiFi devices) to see who is home. And I could of course turn the lights on if some conditions have been met, with mqtt and Node-red. Will let you know my results in the next comment (when items arrive of course). Thanks again for making these videos!

[@thomasvnl]

Hi Ralph. Radar modules arrived today. Tested them out right away and like I said, would come back to you. They work great, but as you mentioned they are very sensitive. I think I'm going to sort that out in software (sort of a debounce). What value was your R6 resistor again? Mine is 2.2K, which seems to trigger the output very frequently.

[@phinok.m.628]

Actually as far as I know those simple movement detectors don't use the doppler effect. Instead they just send microwaves of some frequency. And when the radio waves reflect of things they interfere constructively or destructively with the transmitted wave. And transmitting the wave against the destructive interference draws a little more current than transmitting the wave against constructive interference. When you move the waves are constantly reflected from different distances and angles which cause the current draw of the transmitter to change slightly. And this is what is used to detect movement. In fact these devices don't even have a receiver, all they do is transmit at a specific frequency and monitor the current needed to transmit.

[@RalphBacon]

An interesting point of view, Phino, and not one I would have considered but for all I know you may be right!

[@d00mfish]

Hey, sounds very promising. Do you have any source? I can only find some vague Chinese datasheets :/

[@phinok.m.628]

Hey, sorry for the late reply guys... I honestly haven't found any official sources explaining this, just some spread out bits of information in forum discussions etc. Big clive has done good work reverse engineering this type of sensor in this video: kzbin.info/www/bejne/fpeUapuZbrWnmac Obviously this is a fair bit of speculation. But if you look at the circuitry, this is kinda the only reasonable explanation. There is really no way for it to compare the sent and received signal frequencies for the doppler effect. It doesn't even have a way to receive anything in the first place. And even if it would, the transmitting frequency is within a fairly broad range somewhere but quite random depending on the tolerances of the components used etc. I doubt the frequency is even steady enough for the doppler approach to work reliably. Maybe some motion sensors used to use or still use the doppler effect. But these cheap ones just don't have the hardware for that and also really don't have the necessity. They only wanna know if anything is moving at all, they don't need to know the speed or any further information about the movement. So why should they use the doppler effect? Almost every source on the internet (even Wikipedia) seems to claim these sensors use the doppler effect, none of them however provide any sort of evidence supporting this claim. I have no idea where this myth came from, but it kinda annoys me that everybody just follows along and keeps spreading this information without really questioning it at all. Maybe it uses the doppler effect in some sort of geniusly magical way that I don't understand. If that is the case, I would love for someone to correct me and explain how that works. But as far as I'm concerned these sensors work is fairly simple way and just use all kinds of disturbance created by moving objects, not specifically the doppler effect. To be clear, when I talk about using the doppler effect, I mean measuring the frequency difference between the sent and received signal. The doppler effect is of course always there when something moves within radio or sound waves and of course this will have an effect microwave sensor too in the form of fluctuations in the current draw. But that doesn't mean the sensor specifically uses the doppler effect. Not in the way a radar speed gun for example uses the doppler effect to calculate the speed.

[@joeblow2109]

I was thinking the same thing about IR prism project you are doing....... when it is raining light or hard there's going to be a lite sheet of water on it, not sure how it's going to distinguish light or hard rain, and when the rain stops it will have too dry completely in order for the signal to change. As for me I'm converting an old 3d printer to a small 3000mw laser diode engraver....... changing out the board with a atmega 2560 and a Ramps 1.4 shield...... that was ok but finding the firmware took days.... I'm moving very slow now days. I may order the simpler of microwave modules..... looks like fun. Thanks for the great vids.

[@RalphBacon]

Sounds like you have a lot of things on the go there Joe, as you say it sounds like fun. Thanks for your support and keep watching for new videos every couple of weeks or so.

[@Tsnafu]

Hello Ralph - I'm a bit late to this party but I thought I'd mention in your example of a fire engine doppler effect where the noise "dips then rises again" (0:55) - actually, it doesn't. The pitch changes (lowers) as it passes you, but it doesn't rise again - it stays at that lower pitch as long as it continues to travel away from you at the same speed.

[@RalphBacon]

Do you know what, you're right! When I think about it the fire engine sound doesn't go higher again, does it? Thanks for the correction, Tsnafu!

[@therealchayd]

Great video, I've got a couple of these, and really need a job for them to do. FYI, it was Johnny Mnemonic that had the through-the-door thingy :)

[@RalphBacon]

Ah, yes, Johny Mnemonic, at least I think I remember, but with all this Arduino stuff in my brain my brain cells are full. Both of them.

[@BennyKleykens]

Quite interesting devices but I've been testing that CRWL-0156 thingy (mentioned in anoter post) this weekend and it's super-sensitive and it does not appear to be tuneable below 5 meters which makes them almost useless for in-house purposes unless you find a way to do more directional detection. Which is why lightbulbs that use this technology have aluminum "enclosures'. Note: aluminum packing paper , I've tested it, seems to thin though. Fun to play with but in the end it's probably not more than a gadget/toy.

[@RalphBacon]

The thing is, Benny, the device I used is not supposed to be directional; they make a great thing about it having a 360-degree detection zone. I guess 1mm aluminium should block the signal though (microwaves don't get out of a µwave oven, right?). It probably has a place in security applications (eg if there is movement in your house it might mean burglars are entering via an upstairs window). As you say, though, fun to play with.

[@BennyKleykens]

Yes, I understand. My project is actually to scan if somebody enters the front door. My wife has a problem with her hearing and I wanted to scan the front door and have a light go on in the living room, where she ussually is, so she'd know when somebody comes in. Because there is no power and no ethernet in the hall (could do it with PIR but sending via Wifi proved to battery hungry) I wanted to put this in the room next to the hall and scan through the wall All that worked but ... it also scanned my wife 's movements 10 meters away in the living room! So I tried to limit the range by soldering resistors on the microwave scanner but couldn't get it to - say - a reasonable range of 2 meters so hence I tried to limit it's 360 degree which failed (at least with thin aluminium foil) ... Haven't given up on it yet but the technology has lost much of it's initial appeal ;-)

[@RalphBacon]

I see what you are trying to do. Don't get too disheartened though as your idea seems sound. Try thicker aluminium sheeting or several layers of foil. Or mount it in a metal box with just one side open that is directed at the hallway. You may have to experiment a bit more I guess, but it would be a pity to give up when you're nearly there.

[@robertheal5137]

It is for opening the doors of buildings automatically, and works better than PIR in hot countries.

[@RalphBacon]

And there we have it, Robert, the obvious (now that you've mentioned it) device to detect any movement near a door and open it, Star Trek style. And the actual range (that is, extending beyond the boundaries of a property) just doesn't matter too much in this application. Thanks for posting.

[@mayhem1560]

Hi mate, great channel, slowly working my way through your videos, gets very boring at work lol I just wanted to mention that back in a former life I used to fit intruder alarms and one job would be to replace microwave movement detectors because of the numerous false alarms caused by the detectors picking up movement through doors/walls etc , especially water pipes embedded in the wall would set of alarm if the water was running through the pipe. Again great vids 😂

[@RalphBacon]

I would never have thought that water through pipes would set it off, but I guess it really is movement, right? And the designer(s) of the intruder alarms never thought that would be a problem either! Who knew! I guess they work best in a lead-lined bank vault where the only movement would be that of an intruder attempting access. It's hard to think of other Real World uses where false alarms don't cause considerable problems. Anyway, thanks for posting, Steve, nice to have you on the Arduinite journey!

[@roberteliassen5020]

The antenna on the XYC-WB-DC loos like a waveguide. It's probably not. :) Anyway, interesting stuff. Thanks!

[@RalphBacon]

Hey Robert, how's it hanging? Not sure about this being an actual waveguide, which as the name suggests actually guides the waves into a particular direction. This unit is supposed to have 360-degree coverage. Additionally, the wavelength of a 5.8Ghz signal is about 51mm I believe (let's hope I have not misplaced a decimal point) and that piece of track could be that length given its twisty-turny nature. Just an educated guess... Glad you thought it was interesting and thanks for posting!

[@rayparry5234]

Thanks Ralph. Found it very interesting.

[@RalphBacon]

Hi Raymond! Glad you liked the video, you never know, your next PIR lamp may instead contain one of these units! Thanks for posting.

[@javierpallalorden]

Nice video, I have to try one of those µwave sensors.

[@RalphBacon]

Indeed, Javier, try one (especially the XYC one, it's dead easy to modify). Then you can judge whether it's better than a standard PIR. Or whether detecting your neighbour's cat on its side of the fence is what is really required. Or whether that downside it made up for by the fact that intruders cannot hide behind bushes and things and get away with it. If you try one do post back your experiences, thanks for posting.

[@KnightRiderGuy]

Thanks Ralph for doing these videos. I'm finding the information very useful in helping me to determine what sorts of detectors will work best for our Knight O.S. software for K.I.T.T.'s Surveillance mode.... I'm really wanting to trick that out something fierce so this is very good information :)

[@RalphBacon]

You are most welcome KnightRiderGuy, I'm glad you like the video. Nice to hear from you.

[@huseyint]

Thanks for the video Ralph. Would you please tell me the ideal ohm values that you are happy with for R6 and R9? (Sorry I couldn't get the precise values from the video)

[@RalphBacon]

I'll try, Hüseyin, but as my memory is like a goldfish's we shall see. In my module the resistor that controls sensitivity should be between 10K - 100K (default of 20K) did not have a 20K resistor there at all, it had a 12K which was too sensitive. So I chose a 20K and it worked fine. I used a 1K for the Delay Time which gave a 1 second delay (pulse) when it detected something, just about right for an Arduino sketch. Hope this helps!

[@TheLogasrinivasan]

Hi, Can the XYC - WB -DC or any other sensor's sensitivity can be increased to detect the chest movement while breathing? Thinking of using this sensor in a worst case scenario where people are getting trapped inside the rubble after an earthquake.

[@RalphBacon]

This sensor, as far as I know, was never designed for such uses, Loga. The signal from the tiny movement of a chest, compared to everything else that is moving around would surely be swamped anyway? You can certainly try it, but you would have to shield the unit with a metal case so it only detected in a narrow field of vision - which in itself would make it more difficult to detect what you suggest. But R&D has to start somewhere, so good luck if you decide to proceed.

If you are relying on the Doppler effect, shouldn't your program calculate the change of frequency in order to see if the object is getting closer or farther?

[@RalphBacon]

Hmm, possibly, but this module was tricky enough to work with at it was to detect movement of any kind. There is a library, I believe, that let's you extract the frequency that then might let you determine direction, but it's not something I'd be that interested in investigated further! Check out other comments under this video, I recall there was other information posted by others that may address this. If you get further with your objective do let us all know, it might make this module more useful to others too. Thanks for the question (and apologies that I couldn't really answer it).

[@dheenadayalans9637]

If it is possible can you please post the wiring diagram of the unit with XYZ sensor

[@RalphBacon]

I'm not totally clear what you mean by this, Dheenadayalan. The µwave detector only has 3 connections, two for power and 1 signal pin. There is no XYZ sensor involved here. Perhaps you are thinking of the MPU6060 3-axis Gryo from video #76?

[@FougaFrancois]

for the HB100 , You are using the wrong approach, you should be doing a signal processing library to extract harmonics and work on those ... If you do so, you can go and hunt for the specific thing you want to measure. The HB100 gets it all, from your heart movement to your breathing, it is important to use a library of signal processing, and target your application.

[@RalphBacon]

Hi Francois, I don't suppose you have a link for a suitable Arduino-compatible signal processing library? That approach sounds interesting...

[@FougaFrancois]

Sound a little crazy, you have to extract the DSP part out of the code, but the HB100 does spit audio signal, so, It is fairly adapted to that. The hard part is to figure out how to get the rolling buffer, depending on the platform you are using.

[@joeblow2109]

Just a though .... put a grounded metal can or (dish) around it.... set the sensitivity to the max, point it towards the sky and maybe sense rain?

[@RalphBacon]

Hmm, that *might* work, Joe, but I'm not sure how reliable it would be. Light drizzle vs torrential rain? And what about the sensor that is now pointing to the sky? It would have to have a thin shield to protect it fro the actual rain (which is fine, because as the demo shows the microwaves will go through plastic). Tell you what, buy one and try it out and let us all know the results! Hello, you still there Joe, hello, where have you gone? Heh heh! Nice bit of lateral thinking.

[@lskbgrth4709]

Can i get a reference regarding hb100 code for raspberry. I want to make human detection

[@RalphBacon]

Hi Komanq Liska! Raspberry? As in Pi? I'm afraid I don't have that code as I don't do much with Raspberry Pi boards but if you look at the Arduino sketch you should be able to convert it to run on Python (on a Pi) pretty easily. That's best suggestion I can give you, I'm afraid, but nice of you to stop by.

[@ddjazz]

Hi ralph Very interesting stuff , did you check the current draw of the 2nd unit ? I want to know if its a candidate for a long term battery powered unit.

[@RalphBacon]

Good question! The XYC-WB-DC has a "standby current" (I'm guessing this means no movement detected) of 3mA (states the spec sheet) but no info on run time current (although the transmit power is just 2mW). These are the specs I found: Supply voltage: 3.3V to 20Vdc ● Standby power consumption: less than 3mA ● Sender power: less than 2mW ● operating temperature: -20 ° C to + 80 ° C ● Trigger: (default) repeated trigger ● TTL output: high H> 3.3V, low L 0V ● detection angle: 360 ° (spherical) ● detection range: 6 to 9 meters (default setting is 8 meters) ● Delayed operation: 1 second to a few seconds (default setting is 30 s) I hope this helps.

[@ddjazz]

Ralph S Bacon yes thanks a lot for the info that will come in handy , it looks it should be able to run a few weeks depending on the battery of course without a problem.

[@ابوعمرطوباسي]

i would like to use this idea in my project"smart bump" by using servo motor can you help me

[@RalphBacon]

Well, the idea is that you watch (and indeed replicate) what I do in the demo to increase your understanding and then, having got your project off the ground, you can expand all by yourself. I'm afraid with the best will in the world I don't have time to give general help. I will, however, try and answer specific, video/demo related questions. You may get further help if you go to the Arduino forum, forum.arduino.cc who can provide more general project guidance as well as in-depth coding solutions. Have a visit and good luck with your project!

[@kantyDarius]

hi, great job, i have a cuestion, can i use this device to make distance measures? what's the range of the sensor?

[@RalphBacon]

Ah, no, you can't as far as I know, at least not using the sketch I used, that was for motion only. If you could measure the Doppler signal then I suppose it could be done, and if it can be done you can be sure someone has already done it. Google could be your best friend here, Dario, and if you find out you can do then please let us know! The range of the sensor is large, 6m or more, but can be adjusted. That is why is can be a problem if you only intend to detect movement within a small area, you might be actually detecting movement in the next room, or in the next house!

[@kantyDarius]

thanks Ralph, i'm now beginning with a proyect and want to know how to make a small radar with arduino, lidar lite v3 sensor probably wont be enough for me.

[@vardhanshah]

What would your suggestion be about a best method to detect people through walls effectively?

[@RalphBacon]

This microwave detector would certainly detect people moving, through walls. The trouble is, it would also detect trees, dogs... in fact, _anything_ moving. Do bear in mind though that if your walls are thick concrete or brick then it may struggle to see through them. Simple plasterboard are not a problem.

[@vardhanshah]

@@RalphBacon thank you so much for the valuable piece of information. It'll really help me a lot😄

[@fidudidu2328]

@@vardhanshah In my experience it detects almost anything moving not only in front of the sensor (360°).

[@zeeshanhaider5273]

can it be used as a human motion detector behind a wall and doors??

[@RalphBacon]

That's the idea, Syed, but it will detect movement in a 360-degree circle (or sphere) so you may be detecting things you didn't expect to detect. In my demo I mentioned that I couldn't understand why it was showing movement most of the time - then I realised my ceiling fan was on! Once I'd turned it off, it settled down.

[@KennethElstonBAK]

Other than low range detection through materials (walls books...) or humans. What other applications could this be used for?

[@RalphBacon]

Ah yes, the $64,000 question Kenneth. Now whilst its primary, intended use might be as a replacement for a PIR (alarm) unit, the fact that this detects *all kinds* of movement (not heat-based, such as a warm bodied creature, like the PIR requires) may lend it to other uses. What those uses are are various and manifold I am sure - but I'll leave that for others to come up with the actual ideas. Anyone?

[@johnpossum556]

Trigger for a security camera or lighting? So you don't get false triggers by cats, dogs and racoons would be ideal. I haven't seen a system sold yet that uses this tech in that application. Even better would be to watch areas hard to watch because of tree movements. PIR sucks in these applications and lights stay on wastefully..

[@RalphBacon]

Yes, that sounds sensible. It *could* detect cats, dogs and racoons (not in the UK though because we don't have any) but the sensitivity could be 'adjusted' for that, I guess, in the code. Good to hear from you John.

[@johnpossum556]

There seem to be at least 3 modules being sold on amazon that work on different frequencies. I'm leary of the 2.4 ghz one because isn't that the same freq as wifi? Or is that 2.4 mhz? After posting that I thought to myself " Has any one done an array of sensors?" to get better "sight".... I've never personally worked with arduinos yet but I did get a 37 piece robotics kit to tinker with. Also 45 watts worth of solar panels and some lead acid 12vdc batteries. An arduino is probably in my future. I learned C++ like 20 years ago, though. I never even dreamed it would last this long as a language. Well I'm rambling & digressing. You have a very interesting set of videos, Ralph. I'll try to watch more in my spare time. I appreciate the response. Cheers!

[@jomarilaysontagra8559]

Hello can i use your code for a microwave sensor XYC-WB-D1 thank you for your response

[@RalphBacon]

You might be able to, Jomari, but as I don't have that exact model I can't say for sure. They must be fairly similar though. I suggest comparing the data sheets for both - if they are similar enough just try it out!

[@sarvjitpatil19]

Hi, I'm using RCWL0516 but it detects motion only within limited range and that too in one direction. Can u please help me

[@frankl1955]

I paired the RCWL0516 with a NANO and was able to detect motion through wood doors and plaster walls with a max range of about 15- 20 ft. I needed the NANO to stretch the detection pulses and put it all in a project box and it works pretty well. I needed to shield the back and sides of the box with aluminum foil to make it directional since the RCWL0516 seems to be omnidirectional.

[@RalphBacon]

Indeed, Sarvjit, most microwave detectors are _too_ sensitive and as Frank L has said you usually need to shield them but putting them into a partial metal enclosure (or tin can) to make them directional. So I don't know why yours doesn't work, I suspect the wiring is wrong, you need to double check that.

[@sarvjitpatil19]

@@RalphBacon thanks for ur reply it's working well now. But I want to reduce it's range hoto 20-30 cm how can I do this? Please help

[@TheTechTopics]

@@frankl1955 sir can you give me the code of wood doors and plaster projech

[@poojauday9696]

Hi sir its more informative one. I am going to doing a project regarding vehicle presence detection using microwave radar sensor . Initially going to take arduino as controller . can u suggest from where i can start . Now its the state of literature review. please suggest from where i can start the project. could you please help me to select microwave radar sensor for vehicle presence detection. which sensor is suitable for this

[@RalphBacon]

I have no experience of microwave sensors other than the one I used in this demo, I'm sorry Pooja. However, I would consider why you think a µwave sensor is better than a PIR sensor, or a capacitive sensor. How far are the cars away? Driveway sensor or roadside sensor. Try and give your project some scope before deciding on the technology, that is the best I can say.

[@willwho2512]

That XYC module is most likely to replace the PIR sensor. Check the video from Bigclive as well: kzbin.info/www/bejne/fJjHiYWCn76emZY (And the missing LDR is there)

[@RalphBacon]

Could do, Will, could do. That video from whoever that chap is does describe a similar item indeed, but it's not identical to this one (but the principle most certainly is). At least this device is more or less understandable not just weird! As I mentioned (and BigClive does too in a way) do you actually want a light that switches on because someone is in the room next door? Tricky one this. Thanks for posting and raising this intriguing question.

[@rich1051414]

Seems to make more sense as a motion detector for an alarm system, instead of the typical IR sensors, as long as its range does not extend outside of the walls of the property being protected.

[@notofinterest]

im new to your channel. interesting ide your using. may i ask the name for?

[@RalphBacon]

Hallo Christian, und willkommen! If you look at my channel "Discussion" page you'll find a more complete answer as the first post but let me tell you here that I use the Eclipse IDE (with Arduino add-in). The new version v4 is called "Sloeber", and comes complete with the Arduino add-in. There are a few caveats though, but all in all it's a nice IDE if you are used to something like Visual Studio. The developer has a (gentle) nag screen to contribute and I guess if you use it to make money it would fair to pay up. When Google pays me for this channel I certainly will. So June 2024 is looking good! Thanks for posting, good to hear from you (even if you are upside down) :)

[@notofinterest]

wouw... german sentence :-) many tnx for your answer, i'll need to lookup if this is also available for mac. seems to be a nice ide. the arduino ide isnt bad at all, but ya... missing some features from known webdeveloping ide's. the upside down image isnt a failure... long story but a good one :-) again, tnx for your answer, i'll subscribed the channel and will follow you from now on. regs, chris

[@RalphBacon]

Yes, it's available and works well for the Mac. Thanks for subscribing and one day you will have to tell me the long story about your upside down image. Bis dahin und ich wunsche Dir einen schoenen Tag heute. Now that's a complete sentence. Heh heh! Nice to hear from you Chris.

[@Vhbaske]

You got me if you like cats also!

[@RalphBacon]

Benny is our rescue cat, he's 13 years old and we have had him for the past (almost) 6 years. He is the most adorable and loving cat _ever_ ! And, best of all, he writes all the C++ code for my sketches, amazing!

[@avejst]

? Thanks for sharing😀👍

[@RalphBacon]

Wow, Asger, you really are working your way through my videos, that's brilliant. If you have suggestions for future Arduino-related topics don't be afraid to suggest them. :)

[@ValentinChivu]

Can reduce range until 20 - 25 cm?

[@RalphBacon]

Yes, it worked for me down to just a few centimetres.

[@ValentinChivu]

@@RalphBacon What resistance should I put on them or what else should I do to them? I have seen that it also influences the supply voltage. With 12 volts it is much more sensitive. With 5-6 volts it seems ok but not enough. New I use 1 Mohm. I use RCWL-0516 sensor

[@RalphBacon]

You will have to look at the video again to see what I use. Or see the manufacturers datasheet (perhaps I put more info in my GitHub?).

[@GaryMcKinnonUFO]

@@RalphBacon lol - please think for me! People need to be more attentive.

[@jmitsch44827]

BETTER TO USE THE *** Microwave-Radar-Sensor-RCWL-0516 *** FROM E-BAY ABOUT ONE U.S. DOLLAR EACH I BOUGHT 5 UNITS FOR $3.50 FREE SHIP. THESE ARE MUCH BETTER UNITS NO AMPLIFIER NEEDED, RANGE IS APPROX 15 FT OR 5 M THE ARDUINO SEES THE SIGNAL AND TURNS ON AN LED OR SWITCH. THE UNIT OBSERVED IN THIS VIDEO IS NOT A GOOD PERFORMER. I THINK ANY VOLTAGE COMPACTOR CIRCUIT LIKE THE LM 741 OR 1458 WOULD ALSO WORK FINE TO TURN ON AN LED OR RELAY.

[@RalphBacon]

Interesting post, so I Googled and found this interesting link: hackaday.io/project/19400-first-steps-with-the-rcwl-0516-radar-switch where (scroll to bottom) he discovered the output is analog. Seems like µWave is the PIR of the future then! Thanks for the heads-up, jmitsch44827, good info!

[@rafaelmarroquin4429]

What's name of IDE???

[@RalphBacon]

Hi Rafael!!! The name of the IDE is in fact Eclipse, but you will want the Arduino version: eclipse.baeyens.it/ It will take a bit of installation effort but as you saw it's a great development platform, He does try and persuade you to pay $5 per month (yes, per month) which I think is a bit steep. $20-30 per year maybe, but there we are. Does that help???

[@kellythomas6643]

How do you block it

[@RalphBacon]

Not sure you can. Lead lining, probably.

[@xbb1024]

what about those RFID shielding fabrics?

[@ابوعمرطوباسي]

Hi , can you give me the code

[@RalphBacon]

Hi Abu Omar Abu Omar, you should find all the code here: github.com/RalphBacon/Microwave-Movement-Sensors If anything is missing, let me know!

[@Electronieks]

Julian llet the second

[@RalphBacon]

I don't know whether to be flattered or insulted :) Second as in "second best" or second as in "another, as good as"? Tell you what v12345vtm,, don't clarify, I'll assume the latter!

[@Electronieks]

flattered .... your 're the best ( first ) and jullian is the second