After a few requests, I've made a some modified Pi 4 boards available for people who don't have the time, or equipment to do it themselves. Check them out here: www.ebay.com/itm/114773307539. If you already have a Pi that you want to be modified, I now have a service available for that here: www.etsy.com/shop/FunAndTech
I was chuckling throughout your entire video. I am famous for having terrible manual dexterity. That's why I do software. We might order a couple boards.
@@BoredSleuth Hmm it still works for me. You can try going directly to this listing as well: www.etsy.com/listing/1007434724/modification-service-add-external
Thanks! This saved my day after I found out the all-metal passive-cooling pi case I purchased also completely blocked the wifi signal. I had a self-adhesive antenna not unlike yours lying around and cannibalized a u.FL connector off an old unused GSM board. Works like a charm!
just found this. did this to my pi 4 as the metal case had been tanking the signal strength. i will now be doing this to every pi i work on. its so strange, this is such an easy mod you could almost swear it was supposed to be there. also FCC eat your heart out.
Thanks! Your testing allows me to forget all about doing this altogether. I won't be putting any of my Pi's in metal enclosures. Other than in that particular case the gains provided by the external antenna are pretty minor and certainly not worth the trouble for me. I do appreciate the detail though. Now, if I were to do it I would have absolutely no questions at all about exactly what to do.
Mod worked great on Pi 5. I have an amp I built in a metal enclosure. Adding a PI to it was a great addition however the wifi signal was only about 60%. After the mod I'm getting 90% consistently. Thanks..
Thanks for the inspiration! This video gave me details and courage to try ... I used solder and solder pencil instead of solder paste and hot air, and got it to work, even with shaky hands! Thank you!
Thank you so much for doing all the work and sharing. When I saw that long stub trace left there when the capacitor is removed I thought the designer had made a mistake, or they were just so smart that it was some impedance matching leg or something. I was planning to cut it off as my experience with PCB design made me suspect it would just add a reflection and dork up the signal. Your testing shows the correct solution perfectly. Great engineering work. A shame the original designer wasn't better at layout. The Pi designers likely don't have the resources or high end CAD tools to do really careful PCB layout reviews or analysis.
I found your channel from your comments on a Sabine Hossefelder video (How Dead is Moore's Law?) and I see now why I liked your comment so much. You actually know stuff.
This was awesome to find out! building a large reef aquarium lighting system using a pi for pwm control of 36 different channels of LEDs. thought I would have to mount the pi external to the aluminum housing or have it hardwired to the network...not now!
Hope you enjoyed the video. Feel free to leave a comment if you have any questions. -I'm giving away the modified Pi 4 used in the video along with an antenna, so be sure to enter for a chance to win. There is also an art reference in the video, so put in your guess for an extra entry- gleam.io/AdghM/raspberry-pi-4-with-external-antenna-giveaway -Edit: The giveaway has ended. The winners will be announced shortly, in accordance with the rules of the giveaway.- Edit: Congratulations, Lou from Ohio!
As always very nice video! Interessting to see the how the different ways of disconnecting the internal antenna affects the results. Good measurements and statistic. :-)
What if you fill up the holes of the PCB antenna instead of destroying it ? And/or connect it to the ground.That should transform the antenna into a simple ground metal plate.
I've attempted this on 6x Pi 4s, but I have to admit, the 0201 resistors was quite challenging to install. I'm curious if simply bridging the pads with solder would be just as good? I know it's suggested to use a 0ohm over for example a wire (as mentioned in the video), but given the size of the area, and how close the pads are on the area, would simply soldering not be satisfactory? Appreciate any input. Thanks
Bridging the pads with solder would make a connection at least at DC, but at higher frequencies like those used for WiFi it would likely not be a good quality connection and would result in impedance mismatches. This would cause reflected power which could reduce the performance of the connection.
Resistors in size 0201 must be ordered separately. Why not use a dis-soldered capacitor as a bridge? The trick is working with a lot of flux the 0201 component floats in position.
Me thinking I could do this to the new Pi5...then looking at the board and realising how ridiculously small it is....yeah not sure im going to attempt this lol I was looking for this as my metal case is making the 5Ghz signal drop and fall back to 2.4Ghz..if I take the lid off the case it can stay on 5Ghz
I once tried testing how my smartphone Wi-Fi signal worked from inside a microwave oven. I used a signal strength app and looked through the door. As I recall, there was less change than I (novicely) expected. I was like, wha??? (I don't stand as close to the oven since, 😁) Edit: I tried it again with open door @ -53dBm and closed door @ -83 dBm.
Thanks for the good info. I never compare signals as shown but I just removed the capacitor and put it on the external antenna line. I don't know if it works better if replace the 0 ohm with the removed capacitor. it works though.
It should work fine. At the WiFi frequencies, the capacitor acts essentially like a short (X=1/(2*pi*f*C)). I don't know how it would compare with the other options, but I suspect it would work just fine.
To be specific (since the values are all known), that is a 10pF capacitor and that capacitor at 2.4 GHz has a capacitive reactance of 1/(2*pi*2.4e9*10e-12) = 6.6 Ohms.
@@funtechu I have been used the capacitors for quite a long while. Although it works, I think the performance of 0 ohm resistor can be better. I will try it and compare 0 ohm resistor VS capacitor . TQ.
Soldering that tiny connector was relatively easy even with my primitive soldering tools, but man, I've been struggling with that solder bridge for 20 minutes now
If you can use a tiny piece of wire (like a snipping of a strand from some stranded wire) then that will help. But yeah it's pretty challenging to do with a soldering iron only.
It should work. You would solder the center connector to the pad coming from the Wi-Fi chip, and you would solder the shield to the ground connections on the side. You would also need to be very careful that the coax cable is fixed and doesn't move around a lot otherwise it could end up tearing the trace off the board once they are soldered together
The only thing you didn't test was leave both antennas intact. Which is what I will try on my 4b. Please post your script. This would have made a wireless T shaped emitter. Depending on the physical polarity of the second antenna, and the width between, this antenna may have a much higher directional range. . That said antenna design is almost magic. Without a test pattern it would be hard to see.
I did test that setup during my preliminary checks when designing the experiment because one other commenter on the original follow up video asked about it. However I didn't include it in the final experiment (or this video) because it's a less-than-ideal situation. The issue is that leaving both connected effectively puts them in parallel which means that 1) each antenna gets at most 1/2 the power, and 2) the impedance as seen by the wireless chip is half of the expected value which can result in reflections and cause additional interference. I did run it just for curiosity, but as expected, the results were around 20dB worse than any other option, including stock. As you mention, in theory, the external antenna and internal antenna could be positioned to constructively interfere to increase the directionality. However, it would be more repeatable and easier to just use a good external directional antenna in that case (cantenna, yagi, etc). The script is linked in the description if you want to play around with it.
Hi ! Thank so lot for this very precious video. I wondering, does it possible to solder directly a coaxial cable to the PCB? Without the UFL connector?
Yes, it's possible, though a little tricky. You would need to cut and strip the coax cable and separate out the center connector and the shield. You would connect the shield to the ground plane (where we scrape off the solder mask to make a connection), and the center connector to the center connector pad. Personally I prefer the U.FL connector because it allows easily swapping out antennas, and it ensures that it's a properly impedance-matched system. But soldering on a coax cable is certainly possible.
@@funtechu Hi ! Yes thank's for your answer. Actually, because I don't have air flow soldering machine, to attached directly the cable to the board seems to be easier.
Tis this antenna shared with bluetooth? or is there another bluetooth antenna mod? I really just want my controller to connect well fro across my living room lol
Regarding the 206994-0100 Molex antenna, is it best to orientate these vertically, or horizontally, or with the size/rating, does it not matter? Sorry, I did have a look through the datasheets and went down a google rabbit hole, but I couldn't get a clear answer on this. Thanks again!
If you look at the Application Specification document, pages 10 and 11, you can see the radiation pattern for the antenna for 2.45GHz and 5.5 GHz (two WiFi frequencies). That will show you roughly how to orient the antenna if you have a known position of the other device the antenna will be communicating with.
Do wifi and bluetooth from raspi share the same antenna? If I perform this mod in my raspi, the antenna will support both? My raspi will stay in a metallic case.
Hey Caleb, QQ if that's ok please? Thanks so much for the awesome video, really cool work!!! I'm looking at adding four antennas instead of just one (in order to collect CSI data). Is this possible with this approach please? Thanks a ton!!
Hmm that's not an area of experience for me, but here are some things that may help. The wireless chip used on the Pi4 is BCM43455 which doesn't appear to support multiple antennas (besides externally mixed multi-antenna arrays). I did find this project (github.com/seemoo-lab/nexmon_csi) that supports extracting CSI information, and supports the BMC43455 chip, but that would still only give you information for a single antenna.
@@funtechu Thanks SO much for the brilliant reply Caleb! Really appreciate you looking into this. I guess I could use a USB antenna like this (bit.ly/3sQGnwC) but then it would use a different chip and so defeat the point One follow up question if that's ok, please could you share an example of external mixed multi-antenna arrays please? Am not quite sure what you mean. Many thanks again!
Yes, I'd like to confirm that BT and WiFi signal is better. In my case I'm focused especially on the BT (for Xiaomi BLE temp/humi ensors in entire house). One change is remove 1-st capacitor and solder "hot" antena wire directly to the solder point. My observations is simple and match to performed changes: BLE devices independent of place (external house or garage by the 3 walls) connecting faster and stable. Link quality (RSSI) was increased.
In the video I tested a few suggested ways of doing the modification, including cutting the trace. Cutting the trace gives the best result overall, so it's the recommended way to do the modification.
Yes, the CM4 has the same U.FL connector. You can use the Compute Module Antenna Kit as your antenna after this modification, or any other compatible antenna.
There is only one standard size for U.FL connector to my knowledge, though there are other connector variants (H.FL, E.FL, U.FL-LP, W.FL, etc). Just make sure you are getting one without the LP (low profile) suffix. Assuming that you did order the correct one, keep in mind that some manufacturer's U.FL connectors require much more force to connect than you might think (due to variations in the manufacturing tolerances). Make sure it is properly lined up, and the bottom of the board is supported behind (so you don't damage the board) and push straight down.
@@nickgilbert1264 Ah, yeah that's an incorrect listing. It looks like MHF1 is compatible with U.FL, and MHF2 is compatible with U.FL-LP, but MHF4 is much too small (possibly W.FL compatible, but I can't find a direct comparison chart). Just make sure you get a listing that says U.FL and if it says IPX or IPEX or MHF next to it (which means they are using IPEX connectors instead of Hirose) it should be IPEX 1 or MHF 1.
@@nickgilbert1264 Yeah, that looks correct. If you look at the detail photo which shows the dimensions, the dimensions line up with the dimensions on a standard Hirose U.FL connector, so it should be good as long as that photo is for the item that is being sold. One other thing to double check before you get it, that one is listed as an RP-SMA connector on the other end, so make sure that's compatible with the antenna you have chosen. RP = reverse polarity
You can use any U.FL connector. Here is one on mouser: www.mouser.com/ProductDetail/Linx-Technologies/CONUFL001-SMD-T?qs=EU6FO9ffTwfRdkBeQTdJWQ%3D%3D#.Yk5r0KIE4Fg.link If this is your first time attempting it, you may want to get a couple in case you mess up the first one. And don't forget to get some 0201 0 Ohm jumper resistors while you are at it! The parts cost is going to be way less than the shipping cost for small quantities.
That's mostly going to come down to how long of a U.FL to RP-SMA cable you can find, but a cursory search online shows you can get them up to about 4 feet long so it's theoretically possible. Just keep in mind that the longer the distance from the chip to the antenna, the more loss there will be.
Off topic, but in a weak or interferring instance, do different WiFi channels provide better reception? I'm getting choppy throughput at SSH terminal even though I've placed my RPi in its better location (receiving -49 dBm). The particular channel being used does not have other users. Thanks.
It depends on the band (2.4GHz or 5GHz) but in general choosing a channel that has fewer users will provide better reception (you can use something like InSSIDer to see all wifi signals in your area). One common thing that people overlook is that there are actually only 3 non-overlapping channels for WiFi in 2.4 GHz. They are 1, 6, and 11. If you pick any of the other frequencies (or if your neighbors do) they will harmfully interfere with each other. You can double check this with a wifi spectrum tool, but for example if someone is using channel 4, that will destructively interfere with channels 1 and 6, so in that case channel 11 would probably have the best performance. -49 dBm is decently strong, so it's most likely that you have some interference going on if it isn't working. Look for other 2.4GHz or nearby stuff like microwaves, traditional phone with wireless base station, or baby monitors.
@@funtechu Thankyou. I will test those channels (2.4 GHz). I use a channel utility in an Android app, Traffic Monitor. (I can see, and this answers why channels 1, 6 & 11 are heavily loaded by me - the typical user does not change their router channel). In an completely separate scenario, I had the Pi on top of an HDMI switch - it was giving interference, big time. I changed that arrangement and got back from -61 to -58dBm, and a slight movement forward all of a sudden yielded -49 :-/ With that, it was still choppy :-/ Thanks for your time!
is there an option for doing this with the bluetooth? because the bluetooth on my pi is rather weak when anything gets more than 2 feet away from the device.
I noticed that you started doing this with the Pi 3. Huh. I woulda thought that that lack of a connector was an oversight that they will correct eventually. I guess that's what they wanted to do. OK. Here is my theory. Hobbyists don't need an antenna because they aren't gonna put it in a Faraday cage. So an antenna connector doesn't fit their target market. The Compute Module 4 *does* has an antenna connector. If you want to make a commercial product based on the Pi then you should do something based on the Compute Module. Pretty sensible, I guess. But you cannot buy the compute module anywhere.
Yeah, that seems to be what they were thinking. I suspect the supply chain issue for the compute module 4 is because of the chip shortage issues. Broadcom who makes the main processor is fabless, so they have been having trouble getting fab time. Even the non-compute module versions can be difficult to get depending on the day. And I'll bet since there are companies that have products that were designed around the compute module, that anytime it comes back into stock, they probably immediately sell out.
Great video. Did you use 2.4 GHz or 5.0 GHz? Any differences in these? Also, which antenna part variant are you using? I want to get the same from Mouser, Digikey or Farnell.
These tests were done using 2.4GHz though the modification works with both. I used the Molex part #206994-0100 for these tests, though you can typically use any antenna as long as it 1) has a U.FL connector, 2) is Dual-Band WiFi compatible (2.4GHz and 5GHz), and 3) has a characteristic impedance of 50 ohms.
@@funtechu Thanks. I placed order the same and also Hirose U.FL-R-SMT(01), Vishay CRCW02010000Z0ED resistor and actually also Multicomp Pro MP004561 heatsinked case.
Hehe, I just finished with this. It seems I messed something up XD The solder bridge I chose in the ende was easy peasy for some reason. I just used flux (for the first time in my life) and tiny-tipped soldering iron. Bang, I could not believe I had it with first try. The U.FL connector was for some reason trickier for me. Got the third right. But for some reason the unit does not appear on network. I probably skipped some checks because I was too happy of initial success. I need to check the ring and GND. Tip is firmly ok. I tested conductivity to the first of caps before I scraped off the rest of the line. I'll need to see what is happening on a monitor and re-test ring continuity and antenna seating. If it is really broken, then my hot air gun probably totaled the radio chip. But I will check it again. No regrets!
@@funtechu I tried to took off the antenna cable but it ripped of the whole UFL connector. Then I resoldered the connector. I scraped a bit to expose signal line copper. I measured: No shorts, good conductivity end-to-end. Basically the same situation as before, so I did not anticipate any changes. But when I plugged it in, it came to life! It connected through 2 and half walls, where it previously was struggling like crazy. Now I will cover the whole thing with hot glue so it does not move. Thank you!
Hi Caleb, I'm also interested if this mod will solves or at least minimize this USB3 /2.4ghz/bluetooth issue, in my case I am using a USB3 to NGFF adapter (geekworm x863v2) www.intel.com/content/dam/www/public/us/en/documents/white-papers/usb3-frequency-interference-paper.pdf
This particular antenna has an adhesive backing so you can just peel off the protective paper, and stick it. ESD handling procedures still apply as with any piece of electronics (discharge yourself before working with it, hold by the edges, etc).
@@funtechubut wouldnt the antenna still be suceptible to picking esd while operating not just while mounting as it is a piece of metal exposed in an outside enclosure where it can be touched?
@@anneallison6402 It's certainly possible which is why you should use an appropriate antenna depending on the use. You can get enclosed antennas that don't have exposed connections. The antenna that I show in the video is something you usually put outside of the metal enclosure, but on the inside of a plastic cover or faceplate so it won't be touched. For example, it's the type of antenna that you might find behind the plastic bezel on a laptop.
It depends a lot of which hot air station I'm using, and what solder I'm using. Typically for the hot air station I'm using here, it's around 280C for Sn63/Pb37, and closer to 300C for lead free solders. However, with hot air it's a function of the temperature and the air speed, so you usually have to play around with it a bit on your station to see what works best. The preheater is super important too (I use 100C).
@@funtechu Okay, thanks for the tips ! I will try on test PCBs to see what air speed I can blow and what temperature works the best before causing any damage to the motherboard. Thanks again !
The PI 3 is actually almost identical to the Pi Zero W (Here is that video: ruclips.net/video/Y648CjIiEv8/видео.html). The one difference is you must scrape off the solder mask for the third connection like the Pi 4. You can see what the Pi 3 pad looks like here ruclips.net/video/mZGMGs6RDtc/видео.html Steps: 1. Scratch off solder mask to expose ground connection (similar to this ruclips.net/video/MTwWnZG8wUY/видео.html) 2. Remove the little jumper resistor (ruclips.net/video/Y648CjIiEv8/видео.html) 3. Solder the little jumper resistor so it is now diagonal, and the chip is connected to the external pad (ruclips.net/video/Y648CjIiEv8/видео.html) 4. Solder on the U.FL connector (ruclips.net/video/Y648CjIiEv8/видео.html)
Thanks for the video! Question: Isn't that component you removed from the PCB antenna a 0Ohm resistor that you could just put on the bridge for the ext. antenna? Edit: You said in the video that it is a capacitor. But still, cant the capacitor be used as a bridge since capacitors should pass AC?
Yes, it is a capacitor (not a 0 ohm resistor) and it can theoretically be used to bridge the connection since its resistance is low for high frequencies (Z=1/jw). However, I would recommend using a wire or a 0 ohm resistor so you get the best impedance match and avoid reflections. Those capacitors are used with the PCB antenna to get it to present a 50 ohm impedance overall to the WiFi chip, but since any external antenna you use should already be designed to present a 50 ohm impedance, adding a series capacitor would just cause undesired reflections. I did actually try it out a couple months ago out of curiosity, and it worked, but it gave slightly worse performance overall than the 0 ohm as expected.
@@funtechu Unless you know the value of the capacitor than no you would not reuse it as you will introduce an unknown capacitive element into whatever the impedance the radio sees at that point. Therefore it is best to use a 0 ohm resistor or bridge. Chasing a perfect match is a common mistake anyway though as you can only have everything "perfect" in one particular orientation, in particular surrounds etc etc. Some makers waste huge amounts of time chasing matching networks on their PCB designs that will be wrong as soon as the customer gets the thing into their own case, mount whatever :-) Neat video.
@@robertcargill4533 yes, I do have a modification service listing if you need it. Check it out here: www.etsy.com/listing/1007434724/modification-service-add-external
@@robertcargill4533 If you are doing an ASIAir Pro modification, there is a separate listing for that: www.etsy.com/listing/1013982058/asiair-pro-external-wifi-antenna In that case you would send the whole ASIAir Pro so I can mount the antenna and check that everything works correctly afterwards. Otherwise, if you just want the board modification, you can send just the antenna with the Raspberry Pi and I'll test with that antenna after I'm done.
Yep, it can be done on the 3B+ as well. The pad location is on the bottom of the board as shown here: ruclips.net/video/mZGMGs6RDtc/видео.html. You would just scrape off the solder mask on the side that isn't exposed, solder up the connector, and move the little jumper resistor so the chip is connected to the U.FL connector similar to the Pi Zero W. The microscope view of the area is shown here: ruclips.net/video/mZGMGs6RDtc/видео.html
@@twrfollow-up3701 I think that would be too big. 0201 is the correct size. Note if you are still referring to the Pi3B+, the jumper resistor should already be there, you just have to move it.
@@twrfollow-up3701 You can upload it to some place like imgur and then post the link here if you have questions. Regardless, did you see my previous comment? The second link shows exactly where to make the modification.
Probably near zero. Fiberglass degrades quickly in water, so it pretty quickly disintegrates if it gets in the lungs which is one of the reasons it's reasonably safe.
@@-blackcat-4749 If you are just getting started, then 63/37 leaded solder has the best eutectics and is easier for a beginner. Lead-free solder requires higher temperatures, which can result in more flux vaporization which can be more acutely harmful, so it's important to get the feel and technique of soldering down first. Then you can switch to lead-free solder. Far more important is to make sure you have a good fume extraction system so you are not breathing the flux fumes. Also make sure to wash your hands after soldering to remove any stray lead dust and avoid ingestion.
@@-blackcat-4749 It might be adequate if you only do occasional soldering. Just remember that if at any time you can smell the flux, the ventilation is inadequate. If you end up doing soldering regularly, then getting a proper fume extractor like a Hakko FA-430 is well worth the investment.
After a few requests, I've made a some modified Pi 4 boards available for people who don't have the time, or equipment to do it themselves. Check them out here: www.ebay.com/itm/114773307539. If you already have a Pi that you want to be modified, I now have a service available for that here: www.etsy.com/shop/FunAndTech
I was chuckling throughout your entire video. I am famous for having terrible manual dexterity. That's why I do software.
We might order a couple boards.
@@BoredSleuth Hmm it still works for me. You can try going directly to this listing as well: www.etsy.com/listing/1007434724/modification-service-add-external
Thanks! This saved my day after I found out the all-metal passive-cooling pi case I purchased also completely blocked the wifi signal. I had a self-adhesive antenna not unlike yours lying around and cannibalized a u.FL connector off an old unused GSM board. Works like a charm!
just found this. did this to my pi 4 as the metal case had been tanking the signal strength. i will now be doing this to every pi i work on. its so strange, this is such an easy mod you could almost swear it was supposed to be there. also FCC eat your heart out.
Thanks! Your testing allows me to forget all about doing this altogether. I won't be putting any of my Pi's in metal enclosures. Other than in that particular case the gains provided by the external antenna are pretty minor and certainly not worth the trouble for me. I do appreciate the detail though. Now, if I were to do it I would have absolutely no questions at all about exactly what to do.
Mod worked great on Pi 5. I have an amp I built in a metal enclosure. Adding a PI to it was a great addition however the wifi signal was only about 60%. After the mod I'm getting 90% consistently.
Thanks..
Thanks for the inspiration! This video gave me details and courage to try ... I used solder and solder pencil instead of solder paste and hot air, and got it to work, even with shaky hands! Thank you!
That's awesome to hear!
good job!
Great instructions, exactly what I needed. Testing different conditions was icing on the cake. Mahalo for taking the time and sharing. : )
Glad you found it helpful!
Thank you so much for doing all the work and sharing. When I saw that long stub trace left there when the capacitor is removed I thought the designer had made a mistake, or they were just so smart that it was some impedance matching leg or something. I was planning to cut it off as my experience with PCB design made me suspect it would just add a reflection and dork up the signal. Your testing shows the correct solution perfectly. Great engineering work. A shame the original designer wasn't better at layout. The Pi designers likely don't have the resources or high end CAD tools to do really careful PCB layout reviews or analysis.
I found your channel from your comments on a Sabine Hossefelder video (How Dead is Moore's Law?) and I see now why I liked your comment so much. You actually know stuff.
Welcome!
This was awesome to find out! building a large reef aquarium lighting system using a pi for pwm control of 36 different channels of LEDs. thought I would have to mount the pi external to the aluminum housing or have it hardwired to the network...not now!
Beware of trying this without the proper tools!
It can all go south with the smallest mistake, believe me :)
excellent job Caleb!
Yes. I don't know exactly how, but I killed one Raspi 4B in the first attempt. The second is working nicely.
Works great for extending my BLE range!
This needs a lot more views - excellent work mate
Hope you enjoyed the video. Feel free to leave a comment if you have any questions.
-I'm giving away the modified Pi 4 used in the video along with an antenna, so be sure to enter for a chance to win. There is also an art reference in the video,
so put in your guess for an extra entry-
gleam.io/AdghM/raspberry-pi-4-with-external-antenna-giveaway
-Edit: The giveaway has ended. The winners will be announced shortly, in accordance with the rules of the giveaway.-
Edit: Congratulations, Lou from Ohio!
Ha-ha. I'm glad I found this updated comment... checking my e-mail.
Great explanation and tests. Thanks for creating
As always very nice video! Interessting to see the how the different ways of disconnecting the internal antenna affects the results. Good measurements and statistic. :-)
What if you fill up the holes of the PCB antenna instead of destroying it ? And/or connect it to the ground.That should transform the antenna into a simple ground metal plate.
Very informative video, thank you!!
Awesome ! I need to try the hot air flow technique
I've attempted this on 6x Pi 4s, but I have to admit, the 0201 resistors was quite challenging to install.
I'm curious if simply bridging the pads with solder would be just as good? I know it's suggested to use a 0ohm over for example a wire (as mentioned in the video), but given the size of the area, and how close the pads are on the area, would simply soldering not be satisfactory?
Appreciate any input. Thanks
Bridging the pads with solder would make a connection at least at DC, but at higher frequencies like those used for WiFi it would likely not be a good quality connection and would result in impedance mismatches. This would cause reflected power which could reduce the performance of the connection.
@@funtechu Thanks. Much appreciate the response.
Resistors in size 0201 must be ordered separately. Why not use a dis-soldered capacitor as a bridge?
The trick is working with a lot of flux the 0201 component floats in position.
Thank you for the Review :) hopefully you get some 2 and 4 gig boards in soon.
We can hope. The backorder dates are way in the future right now, so it's mostly luck when stuff gets back in stock.
Me thinking I could do this to the new Pi5...then looking at the board and realising how ridiculously small it is....yeah not sure im going to attempt this lol
I was looking for this as my metal case is making the 5Ghz signal drop and fall back to 2.4Ghz..if I take the lid off the case it can stay on 5Ghz
I once tried testing how my smartphone Wi-Fi signal worked from inside a microwave oven. I used a signal strength app and looked through the door. As I recall, there was less change than I (novicely) expected. I was like, wha??? (I don't stand as close to the oven since, 😁)
Edit: I tried it again with open door @ -53dBm and closed door @ -83 dBm.
Thanks for the good info. I never compare signals as shown but I just removed the capacitor and put it on the external antenna line. I don't know if it works better if replace the 0 ohm with the removed capacitor. it works though.
It should work fine. At the WiFi frequencies, the capacitor acts essentially like a short (X=1/(2*pi*f*C)). I don't know how it would compare with the other options, but I suspect it would work just fine.
To be specific (since the values are all known), that is a 10pF capacitor and that capacitor at 2.4 GHz has a capacitive reactance of 1/(2*pi*2.4e9*10e-12) = 6.6 Ohms.
@@funtechu Thanks for your reply , yes, the XC is high indeed.
@@myaquaponic5206 Sorry if I was unclear that wasn't my intended meaning. 6 ohms isn't particularly high, hence why it's working
@@funtechu I have been used the capacitors for quite a long while. Although it works, I think the performance of 0 ohm resistor can be better. I will try it and compare 0 ohm resistor VS capacitor . TQ.
Has anyone got the internal WiFi adapter to work using WPA3?
Soldering that tiny connector was relatively easy even with my primitive soldering tools, but man, I've been struggling with that solder bridge for 20 minutes now
If you can use a tiny piece of wire (like a snipping of a strand from some stranded wire) then that will help. But yeah it's pretty challenging to do with a soldering iron only.
If I don't use a connector, if I solder directly the wire from the antenna (included), will it not break the impedance matching? Will work?
It should work. You would solder the center connector to the pad coming from the Wi-Fi chip, and you would solder the shield to the ground connections on the side. You would also need to be very careful that the coax cable is fixed and doesn't move around a lot otherwise it could end up tearing the trace off the board once they are soldered together
@@funtechu Thanks a lot for your answer. Yes, I know that when soldering to the tracks, you should use a glue gun after.
The only thing you didn't test was leave both antennas intact.
Which is what I will try on my 4b.
Please post your script.
This would have made a wireless T shaped emitter. Depending on the physical polarity of the second antenna, and the width between, this antenna may have a much higher directional range. .
That said antenna design is almost magic. Without a test pattern it would be hard to see.
I did test that setup during my preliminary checks when designing the experiment because one other commenter on the original follow up video asked about it. However I didn't include it in the final experiment (or this video) because it's a less-than-ideal situation. The issue is that leaving both connected effectively puts them in parallel which means that 1) each antenna gets at most 1/2 the power, and 2) the impedance as seen by the wireless chip is half of the expected value which can result in reflections and cause additional interference. I did run it just for curiosity, but as expected, the results were around 20dB worse than any other option, including stock.
As you mention, in theory, the external antenna and internal antenna could be positioned to constructively interfere to increase the directionality. However, it would be more repeatable and easier to just use a good external directional antenna in that case (cantenna, yagi, etc).
The script is linked in the description if you want to play around with it.
@@funtechu thanks for the reply.
My setup is running manjaro arm64.
Getting it tweaked is interesting
Simply pulling the old antenna to ground should remove any worries of it interfering.
Hi ! Thank so lot for this very precious video. I wondering, does it possible to solder directly a coaxial cable to the PCB? Without the UFL connector?
Yes, it's possible, though a little tricky. You would need to cut and strip the coax cable and separate out the center connector and the shield. You would connect the shield to the ground plane (where we scrape off the solder mask to make a connection), and the center connector to the center connector pad.
Personally I prefer the U.FL connector because it allows easily swapping out antennas, and it ensures that it's a properly impedance-matched system. But soldering on a coax cable is certainly possible.
@@funtechu Hi ! Yes thank's for your answer. Actually, because I don't have air flow soldering machine, to attached directly the cable to the board seems to be easier.
Brave, brave man! hehe
Tis this antenna shared with bluetooth? or is there another bluetooth antenna mod? I really just want my controller to connect well fro across my living room lol
Yes, this antenna is used for both WiFi and Bluetooth on the Pi.
Regarding the 206994-0100 Molex antenna, is it best to orientate these vertically, or horizontally, or with the size/rating, does it not matter?
Sorry, I did have a look through the datasheets and went down a google rabbit hole, but I couldn't get a clear answer on this.
Thanks again!
If you look at the Application Specification document, pages 10 and 11, you can see the radiation pattern for the antenna for 2.45GHz and 5.5 GHz (two WiFi frequencies). That will show you roughly how to orient the antenna if you have a known position of the other device the antenna will be communicating with.
Do wifi and bluetooth from raspi share the same antenna? If I perform this mod in my raspi, the antenna will support both? My raspi will stay in a metallic case.
Yes, they use the same antenna, so the improvements apply to both WiFi and Bluetooth
@@funtechu awesome, I was about to buy two USB adapters with antennas, one for each. You saved me, thanks!
Hey Caleb, QQ if that's ok please? Thanks so much for the awesome video, really cool work!!! I'm looking at adding four antennas instead of just one (in order to collect CSI data). Is this possible with this approach please? Thanks a ton!!
Hmm that's not an area of experience for me, but here are some things that may help. The wireless chip used on the Pi4 is BCM43455
which doesn't appear to support multiple antennas (besides externally mixed multi-antenna arrays). I did find this project (github.com/seemoo-lab/nexmon_csi) that supports extracting CSI information, and supports the BMC43455 chip, but that would still only give you information for a single antenna.
@@funtechu Thanks SO much for the brilliant reply Caleb! Really appreciate you looking into this. I guess I could use a USB antenna like this (bit.ly/3sQGnwC) but then it would use a different chip and so defeat the point
One follow up question if that's ok, please could you share an example of external mixed multi-antenna arrays please? Am not quite sure what you mean.
Many thanks again!
Thank you for sharing! Would this increase bluetooth preformance also?
Yes it should. WiFi and bluetooth use the same antenna.
Yes, I'd like to confirm that BT and WiFi signal is better. In my case I'm focused especially on the BT (for Xiaomi BLE temp/humi ensors in entire house). One change is remove 1-st capacitor and solder "hot" antena wire directly to the solder point. My observations is simple and match to performed changes: BLE devices independent of place (external house or garage by the 3 walls) connecting faster and stable. Link quality (RSSI) was increased.
Sad that Raspbery Pi designers didn't put an external antenna port on the board. It seems like an obvious thing.
RUclips really be recommending videos with 442 views. Good job youtube!
443 now ;)
What's the reason you used a 100mm antenna, instead of a full-wavelength (125mm)?
100mm is the length of the coax cable, not the antenna.
thx
Just wondering why not just cut the trace why would you need to remove the caps
In the video I tested a few suggested ways of doing the modification, including cutting the trace. Cutting the trace gives the best result overall, so it's the recommended way to do the modification.
not pretty but i got this working thanks
Do you know if that's the same connector as on the CM4?
Yes, the CM4 has the same U.FL connector. You can use the Compute Module Antenna Kit as your antenna after this modification, or any other compatible antenna.
Thanks for instructions. Can i use this for Bluetooth?
Yes, the same antenna is shared by WiFi and Bluetooth
There seems to be more than one size of U.FL connector. The pigtails I've ordered don't fit. Does anyone know what to google to get the correct size?
There is only one standard size for U.FL connector to my knowledge, though there are other connector variants (H.FL, E.FL, U.FL-LP, W.FL, etc). Just make sure you are getting one without the LP (low profile) suffix.
Assuming that you did order the correct one, keep in mind that some manufacturer's U.FL connectors require much more force to connect than you might think (due to variations in the manufacturing tolerances). Make sure it is properly lined up, and the bottom of the board is supported behind (so you don't damage the board) and push straight down.
@@funtechu I guess this Amazon description is misleading as it mentions both U.FL and MHF4: amzn.to/3h3Y875
This is the one which is too small.
@@nickgilbert1264 Ah, yeah that's an incorrect listing. It looks like MHF1 is compatible with U.FL, and MHF2 is compatible with U.FL-LP, but MHF4 is much too small (possibly W.FL compatible, but I can't find a direct comparison chart).
Just make sure you get a listing that says U.FL and if it says IPX or IPEX or MHF next to it (which means they are using IPEX connectors instead of Hirose) it should be IPEX 1 or MHF 1.
@@funtechu Do you think this is the right cable? - amzn.to/2T6XtJR
@@nickgilbert1264 Yeah, that looks correct. If you look at the detail photo which shows the dimensions, the dimensions line up with the dimensions on a standard Hirose U.FL connector, so it should be good as long as that photo is for the item that is being sold.
One other thing to double check before you get it, that one is listed as an RP-SMA connector on the other end, so make sure that's compatible with the antenna you have chosen. RP = reverse polarity
I ordered the Raspberry Pi antenna but it did not come with the surface mount connector to go on the circuit board. Where do I get one?
You can use any U.FL connector. Here is one on mouser: www.mouser.com/ProductDetail/Linx-Technologies/CONUFL001-SMD-T?qs=EU6FO9ffTwfRdkBeQTdJWQ%3D%3D#.Yk5r0KIE4Fg.link
If this is your first time attempting it, you may want to get a couple in case you mess up the first one. And don't forget to get some 0201 0 Ohm jumper resistors while you are at it!
The parts cost is going to be way less than the shipping cost for small quantities.
Does it matter how long the cable is? I've got a pi in a van and I need an antenna too put on top will any wifi antenna work okay?
That's mostly going to come down to how long of a U.FL to RP-SMA cable you can find, but a cursory search online shows you can get them up to about 4 feet long so it's theoretically possible. Just keep in mind that the longer the distance from the chip to the antenna, the more loss there will be.
Off topic, but in a weak or interferring instance, do different WiFi channels provide better reception? I'm getting choppy throughput at SSH terminal even though I've placed my RPi in its better location (receiving -49 dBm). The particular channel being used does not have other users. Thanks.
It depends on the band (2.4GHz or 5GHz) but in general choosing a channel that has fewer users will provide better reception (you can use something like InSSIDer to see all wifi signals in your area).
One common thing that people overlook is that there are actually only 3 non-overlapping channels for WiFi in 2.4 GHz. They are 1, 6, and 11. If you pick any of the other frequencies (or if your neighbors do) they will harmfully interfere with each other. You can double check this with a wifi spectrum tool, but for example if someone is using channel 4, that will destructively interfere with channels 1 and 6, so in that case channel 11 would probably have the best performance.
-49 dBm is decently strong, so it's most likely that you have some interference going on if it isn't working. Look for other 2.4GHz or nearby stuff like microwaves, traditional phone with wireless base station, or baby monitors.
@@funtechu Thankyou. I will test those channels (2.4 GHz). I use a channel utility in an Android app, Traffic Monitor. (I can see, and this answers why channels 1, 6 & 11 are heavily loaded by me - the typical user does not change their router channel).
In an completely separate scenario, I had the Pi on top of an HDMI switch - it was giving interference, big time. I changed that arrangement and got back from -61 to -58dBm, and a slight movement forward all of a sudden yielded -49 :-/ With that, it was still choppy :-/
Thanks for your time!
is there an option for doing this with the bluetooth? because the bluetooth on my pi is rather weak when anything gets more than 2 feet away from the device.
The Bluetooth uses the same antenna, so this should work for that as well.
I noticed that you started doing this with the Pi 3. Huh. I woulda thought that that lack of a connector was an oversight that they will correct eventually. I guess that's what they wanted to do.
OK. Here is my theory. Hobbyists don't need an antenna because they aren't gonna put it in a Faraday cage. So an antenna connector doesn't fit their target market.
The Compute Module 4 *does* has an antenna connector. If you want to make a commercial product based on the Pi then you should do something based on the Compute Module. Pretty sensible, I guess. But you cannot buy the compute module anywhere.
Yeah, that seems to be what they were thinking. I suspect the supply chain issue for the compute module 4 is because of the chip shortage issues. Broadcom who makes the main processor is fabless, so they have been having trouble getting fab time. Even the non-compute module versions can be difficult to get depending on the day. And I'll bet since there are companies that have products that were designed around the compute module, that anytime it comes back into stock, they probably immediately sell out.
Great video. Did you use 2.4 GHz or 5.0 GHz? Any differences in these? Also, which antenna part variant are you using? I want to get the same from Mouser, Digikey or Farnell.
These tests were done using 2.4GHz though the modification works with both. I used the Molex part #206994-0100 for these tests, though you can typically use any antenna as long as it 1) has a U.FL connector, 2) is Dual-Band WiFi compatible (2.4GHz and 5GHz), and 3) has a characteristic impedance of 50 ohms.
@@funtechu Thanks. I placed order the same and also Hirose U.FL-R-SMT(01), Vishay CRCW02010000Z0ED resistor and actually also Multicomp Pro MP004561 heatsinked case.
Hehe, I just finished with this. It seems I messed something up XD The solder bridge I chose in the ende was easy peasy for some reason. I just used flux (for the first time in my life) and tiny-tipped soldering iron. Bang, I could not believe I had it with first try. The U.FL connector was for some reason trickier for me. Got the third right. But for some reason the unit does not appear on network. I probably skipped some checks because I was too happy of initial success. I need to check the ring and GND. Tip is firmly ok. I tested conductivity to the first of caps before I scraped off the rest of the line. I'll need to see what is happening on a monitor and re-test ring continuity and antenna seating. If it is really broken, then my hot air gun probably totaled the radio chip. But I will check it again. No regrets!
@@JannePaalijarvi Hopefully you can figure it out :)
@@funtechu I tried to took off the antenna cable but it ripped of the whole UFL connector. Then I resoldered the connector. I scraped a bit to expose signal line copper. I measured: No shorts, good conductivity end-to-end. Basically the same situation as before, so I did not anticipate any changes. But when I plugged it in, it came to life! It connected through 2 and half walls, where it previously was struggling like crazy. Now I will cover the whole thing with hot glue so it does not move. Thank you!
Has anyone seen this mod give any improvement to the USB3 wifi interference issues the PI4 has?
Hi Caleb, I'm also interested if this mod will solves or at least minimize this USB3 /2.4ghz/bluetooth issue, in my case I am using a USB3 to NGFF adapter (geekworm x863v2) www.intel.com/content/dam/www/public/us/en/documents/white-papers/usb3-frequency-interference-paper.pdf
What about esd protection and installation of that particular antenna you use (like how to stick it to a case )?
This particular antenna has an adhesive backing so you can just peel off the protective paper, and stick it. ESD handling procedures still apply as with any piece of electronics (discharge yourself before working with it, hold by the edges, etc).
@@funtechubut wouldnt the antenna still be suceptible to picking esd while operating not just while mounting as it is a piece of metal exposed in an outside enclosure where it can be touched?
@@anneallison6402 It's certainly possible which is why you should use an appropriate antenna depending on the use. You can get enclosed antennas that don't have exposed connections. The antenna that I show in the video is something you usually put outside of the metal enclosure, but on the inside of a plastic cover or faceplate so it won't be touched. For example, it's the type of antenna that you might find behind the plastic bezel on a laptop.
Hi, what temperature do you use to melt the Sn/Pb paste with your hot air gun ?
It depends a lot of which hot air station I'm using, and what solder I'm using. Typically for the hot air station I'm using here, it's around 280C for Sn63/Pb37, and closer to 300C for lead free solders. However, with hot air it's a function of the temperature and the air speed, so you usually have to play around with it a bit on your station to see what works best. The preheater is super important too (I use 100C).
@@funtechu Okay, thanks for the tips ! I will try on test PCBs to see what air speed I can blow and what temperature works the best before causing any damage to the motherboard. Thanks again !
Is there a way to add another connector, to add an external wifi and external bluetooth antennae?
The same connector works for both WiFi and bluetooth (it is shared)
@@funtechu do you know why I would have 2 antennas in my AIO monitor, and two connectors on the atheros AR5B22 board they’re connected to?
@@funtechu great job on this BTW!
could it be IR for the remote and keyboard?
@@SeanFitzthum IR is optical so that's a different type of interface
Hi Caleb could you do one on the ft3 I saw your video but I don't speak English so it's hard to understand thanks
The PI 3 is actually almost identical to the Pi Zero W (Here is that video: ruclips.net/video/Y648CjIiEv8/видео.html). The one difference is you must scrape off the solder mask for the third connection like the Pi 4. You can see what the Pi 3 pad looks like here ruclips.net/video/mZGMGs6RDtc/видео.html
Steps:
1. Scratch off solder mask to expose ground connection (similar to this ruclips.net/video/MTwWnZG8wUY/видео.html)
2. Remove the little jumper resistor (ruclips.net/video/Y648CjIiEv8/видео.html)
3. Solder the little jumper resistor so it is now diagonal, and the chip is connected to the external pad (ruclips.net/video/Y648CjIiEv8/видео.html)
4. Solder on the U.FL connector (ruclips.net/video/Y648CjIiEv8/видео.html)
@@funtechu merci
Thanks for the video!
Question: Isn't that component you removed from the PCB antenna a 0Ohm resistor that you could just put on the bridge for the ext. antenna?
Edit: You said in the video that it is a capacitor. But still, cant the capacitor be used as a bridge since capacitors should pass AC?
Yes, it is a capacitor (not a 0 ohm resistor) and it can theoretically be used to bridge the connection since its resistance is low for high frequencies (Z=1/jw). However, I would recommend using a wire or a 0 ohm resistor so you get the best impedance match and avoid reflections. Those capacitors are used with the PCB antenna to get it to present a 50 ohm impedance overall to the WiFi chip, but since any external antenna you use should already be designed to present a 50 ohm impedance, adding a series capacitor would just cause undesired reflections. I did actually try it out a couple months ago out of curiosity, and it worked, but it gave slightly worse performance overall than the 0 ohm as expected.
@@funtechu Unless you know the value of the capacitor than no you would not reuse it as you will introduce an unknown capacitive element into whatever the impedance the radio sees at that point. Therefore it is best to use a 0 ohm resistor or bridge.
Chasing a perfect match is a common mistake anyway though as you can only have everything "perfect" in one particular orientation, in particular surrounds etc etc. Some makers waste huge amounts of time chasing matching networks on their PCB designs that will be wrong as soon as the customer gets the thing into their own case, mount whatever :-) Neat video.
"Like if you liked" 👍🏼
Morning..I dont have a resistor at hand for this mod, what size wire will work for this in place of the resistor?? Thanks
You could just use a single strand out of some finely stranded wire and then trim it down. Actual diameter is really small, perhaps a 26 or 28AWG
@@funtechu I'm having difficulty trying to add wire to the board, can you do this for me, and I'll be happy to pay you too
@@robertcargill4533 yes, I do have a modification service listing if you need it. Check it out here: www.etsy.com/listing/1007434724/modification-service-add-external
@@funtechu Thanks, do I need to send the entire ASIair Pro to you and the antenna so you can verify it's working correctly?
@@robertcargill4533 If you are doing an ASIAir Pro modification, there is a separate listing for that: www.etsy.com/listing/1013982058/asiair-pro-external-wifi-antenna
In that case you would send the whole ASIAir Pro so I can mount the antenna and check that everything works correctly afterwards. Otherwise, if you just want the board modification, you can send just the antenna with the Raspberry Pi and I'll test with that antenna after I'm done.
Hi Caleb, Can I do the same modification for Rpi 3 Model B+ since the onboard antenna is similar to the one on your video?
Yep, it can be done on the 3B+ as well. The pad location is on the bottom of the board as shown here: ruclips.net/video/mZGMGs6RDtc/видео.html. You would just scrape off the solder mask on the side that isn't exposed, solder up the connector, and move the little jumper resistor so the chip is connected to the U.FL connector similar to the Pi Zero W. The microscope view of the area is shown here: ruclips.net/video/mZGMGs6RDtc/видео.html
@@funtechu Thanks for the information. Will 0Ohm 0805 Ok to bridge the middle connector?
@@twrfollow-up3701 I think that would be too big. 0201 is the correct size. Note if you are still referring to the Pi3B+, the jumper resistor should already be there, you just have to move it.
@@funtechu yes I am referring to Rpi3B+ kindly send me your email id to send a picture of the onboard antenna.
@@twrfollow-up3701 You can upload it to some place like imgur and then post the link here if you have questions. Regardless, did you see my previous comment? The second link shows exactly where to make the modification.
PI3
Extra WiFi Antenna?Perfect, because i have a giant heatsink that will Block the WiFi chip
Great video (except for the awful way of speaking "Vocal Fry" which seems to be in fashion and that everyone tries to reproduce)
very good info but you can simply say "no, you cannot add external antenna" :)
📁 The other boring case. An everyday thing
Probably near zero. Fiberglass degrades quickly in water, so it pretty quickly disintegrates if it gets in the lungs which is one of the reasons it's reasonably safe.
🔖 That was a unchanging demonstration. Another typical day
@@-blackcat-4749 If you are just getting started, then 63/37 leaded solder has the best eutectics and is easier for a beginner. Lead-free solder requires higher temperatures, which can result in more flux vaporization which can be more acutely harmful, so it's important to get the feel and technique of soldering down first. Then you can switch to lead-free solder.
Far more important is to make sure you have a good fume extraction system so you are not breathing the flux fumes. Also make sure to wash your hands after soldering to remove any stray lead dust and avoid ingestion.
This 📕 is a customary occurrence. Nothing special
@@-blackcat-4749 It might be adequate if you only do occasional soldering. Just remember that if at any time you can smell the flux, the ventilation is inadequate. If you end up doing soldering regularly, then getting a proper fume extractor like a Hakko FA-430 is well worth the investment.