Great explanation of SMA and RP-SMA thrown in there. Thanks for all the great esp8266 videos
@AndreasSpiess8 жыл бұрын
You're welcome. I was amused when I read about the RP story. That's why I included it.
@joegrant99913 жыл бұрын
@@AndreasSpiess pö
@AllanKobelansky7 жыл бұрын
Andreas, have you ever mentioned what your profession is? There are many DIY and so-called "experts" on KZbin, but your work is quite well presented and researched. Or is that just your Swiss genes?
@AndreasSpiess7 жыл бұрын
+Allan Kobelansky In my youth I was a trained electronics engineer, but lost a little track during the "family phase". So, now I consider myself as an interested hobbyist.
@AllanKobelansky7 жыл бұрын
Andreas Spiess As an experienced electrical engineer with post graduate degrees, I re-knight you as an "electronics engineer". Your work is beyond hobbyist level.
@AndreasSpiess7 жыл бұрын
+Allan Kobelansky Thanks! :-)
@eu47647 жыл бұрын
I'm with you Allan Kobelansky. There is a very clear difference!
@xgrapher4 жыл бұрын
why do you wanna marry him?
@Inquire984 жыл бұрын
"Thank GOD", and thank you for your support and time 😉 This video is VERY interesting and useful 😎
@AndreasSpiess4 жыл бұрын
You are welcome!
@Thomodian4 жыл бұрын
it is impressive that you can transmit to distance of 150m with only 3.3 volts. Maybe some aluminium parabola behind the antenna could even improve it in some direction.
@AndreasSpiess4 жыл бұрын
If you are interested in distance with 3.3 volt I suggest you watch my world record or my satellite video...
@nathanas644 жыл бұрын
These videos are so interesting to hobbyists and life long learners. I’m tempted to create a LORA setup with yagi antennas to improve the range.
@AndreasSpiess4 жыл бұрын
You can watch my LoRa videos and then decide if this helps.
@MJ12GRAVITON8 жыл бұрын
You always have great videos that I very much enjoy, thank you Andreas.
@AndreasSpiess8 жыл бұрын
+Graviton_144 Grav Thank you for your nice comment!
@dsp43928 жыл бұрын
Great info. Plus your house looks gorgeous. I mean, an undergound bunker _and_ a roof garden? That's just amazing.
@AndreasSpiess8 жыл бұрын
The house is very small. And the bunker/garage is for the more than 100 other families living in the same estate. But it is ok for us...
@buzhug352 жыл бұрын
Dear Andreas, Another intresting vidéo… as usual. I’m making some tests on a raspberry pi with an external antenna and results are significants : antenna is the heart of a transmit system! I was surprized that the position for a connector was on the board! With a few modifications (and sweat because it’s very small !), we can make some good tests about antennes. Thank you for your job. Best regards Jean-Michel
@AndreasSpiess2 жыл бұрын
Glad you enjoy experimenting with antennas. You find many other videos about antennas on this channel, BTW...
@ModestMaker6 жыл бұрын
Wow - you answer my questions even before I ask them. You have an amazing suite of videos - thank you!
@AndreasSpiess6 жыл бұрын
And this answer was produced a long time ago. I hope I will be able to add another chapter to this topic soon...
@MdAshik-up6iv4 жыл бұрын
@@AndreasSpiess good work
@MobiusHorizons8 жыл бұрын
I think the critical difference between this test an cnlohr's test is that he used an access point as one end of the connection. This changes things rather dramatically I would assume since access points are powered and can create a substantially stronger signal than a battery powered device. I would imagine they can amplify weaker return signals as well, although I do not know that for a fact.
@AndreasSpiess8 жыл бұрын
I did not want to have a record as cnlohr. I just wanted to test a real scenario. cnlohr's work, however, is very interesting!
@MobiusHorizons8 жыл бұрын
+Andreas Spiess I guess I always try to connect my esp to the internet for connectivity, so in my case having one side be the AP is realistic for me. Cool video, thanks for doing the test.
@muppetpaster5 жыл бұрын
a battery powered device isn't powered??
@DiyintheGhetto8 жыл бұрын
Awesome Video Andreas as always. I'm getting the same as you do. I think the reason why CNLohr's got more is because he took a Router on the road with him and that router has a high gain patch antenna on it. But other wise it would of gotten the same results as you did if the test was done the same.
@AndreasSpiess8 жыл бұрын
+joseph chrzempiec (josephchrzempiec) Thanks for your fast reply. You are right about his antenna. And in addition, he just did something like a ping test. But anyway, I think, his results are very impressive.
@DiyintheGhetto8 жыл бұрын
If can get that range would be awesome. But in this case it will need a boost from a external antenna and some kind of booster i would think.
@mr.0x3732 жыл бұрын
Very well explained!I was able to get 50m with a clear line of sight on the esp8266-01.
@AndreasSpiess2 жыл бұрын
Thank you for sharing your experience!
@remove_kippa95783 жыл бұрын
👏 noob here, and wanted to say thank you for all of the informational videos
@AndreasSpiess3 жыл бұрын
Glad you like them!
@Regimantas_Baublys7 жыл бұрын
My test with pcb antena 500m. Set to b mode and increase tx power to max :)
@AndreasSpiess7 жыл бұрын
Thanks for the feedback. I think, the "receiving" station is also important and the Ipad I used is probably not the best...
@dougtaylor95166 жыл бұрын
Hi Swiss Guy! I think your test proves more about Apple's policy around wifi than anything else. I have achieved similar results to Mr Laur (spelling?) using an ESP-01 with trace antenna and an Android device as the client. Apple have dumbed down their wifi reception because they don't want to operate in the shady -70dB (more or less - I don't know the exact figure) zone because they feel the bad network experience will reflect badly on their devices. So they rather let you connect only when the signal is a bit stronger and less likely to drop. If you repeat your tests with any other client device I think your range will double (at least). You may then also see more advantage with the ESP-07. Thanks for your always excellent videos. You have fans in South Africa... all my IoT friends enjoy your stuff. We have a request... one day will you tell us a joke? Maybe at the end of a video, just for fun ;)
@AndreasSpiess6 жыл бұрын
Thanks for the update. Jokes are never easy on an international basis... BTW: Yesterday I met a very nice guy from SA in Amsterdam at the LoRa convention :-)
@adivacaru8 жыл бұрын
Hi, you can use a helical antenna to your modules and you will increase your range dramatically but it's directional, the longer it is the more directional
@AndreasSpiess8 жыл бұрын
I have some material laying around to play with different antennas. But, unfortunatley, for the moment, I do not have the time. Subscribe and you will probably see a video in some future...
@asmolbean93004 жыл бұрын
You seem like such a great guy, if you have kids they're lucky to have such a nice dad :) Also I love the way you say bye at the end ...makes me smile everytime idk why lol
@AndreasSpiess4 жыл бұрын
Thank you for your nice words! I will tell it to my kids ;-)
@jeffbeck65016 жыл бұрын
I like your work, but I love CNLohr's work.
@AndreasSpiess6 жыл бұрын
:-)
@TechNed5 жыл бұрын
'Jeff Beck Group' was great work.
@vks0027 жыл бұрын
Hi Andreas, I have been watching your videos for some time now and they are wonderful. As someone else commented here, they are simple, nicely explained and very practical. And thanks for this one too. I have also been trying to find out the range of these ESPs in my house which is ground + first floor for my automation project, so this will help.
@AndreasSpiess7 жыл бұрын
Thanks for your nice words! In-house, the range depends of course from many things...
@rekall764 жыл бұрын
during initial r&d of some recent work i did using wemos d1 mini (esp8266 12-f) modules, i was able to retain a connection to the back office, through our front office door, and about 50 feet down the hall... i was pleasantly surprised.
@AndreasSpiess4 жыл бұрын
If you have some sort of „line of sight“, these small modules can bridge quits a distance...
@grimtagnbag5 ай бұрын
Bro you are in my head. I have a question and you already have a video. You are Awsome
@AndreasSpiess5 ай бұрын
Cool!
@grimtagnbag5 ай бұрын
Esp32 about the same range? Cause I’m working on a drone dropper for the Dji mini 2. Got the servo running using a webpage to control it.
@AndreasSpiess5 ай бұрын
@@grimtagnbag Yes
@Slider27328 жыл бұрын
Excellent info. For my tests...with ESP-01 on bed in bedroom, through wooden walls of house, I get > 400ft (120m). But, that's when using a Samsung Tribute phone and i would think the receiver in the phone has something to do with range. Same for your iPad. An ESP-03 in my latest video blew its ceramic antenna, so I removed it and soldered a tiny wire to the antenna output pin of the ESP-03 chip. Then fitted an antenna cut from another ESP-01...range tripled to similar to the other ESP-01
@AndreasSpiess8 жыл бұрын
+slider2732 You are right. The antenna of the receiver has exactly the same importance thant the one of the sender. I do not know the ESP-03 but I own some ESP-07 with a ceramic antenna. So far, I did not check the performance of those because I like the -07 because it has an antenna plug for an external antenna
@neogeo82676 жыл бұрын
Coax and connections at these frequencies = massive reduction in output power. Try to keep it as short as possible and solder when possible to reduce insertion loss. I'd love to see the same experiment repeated with the native board, antenna w/ connect + coax, and then antenna soldered as directly as possible. I really enjoy your videos - thank you - subscribed
@AndreasSpiess6 жыл бұрын
In the meantime, I made a few videos about wireless and antennas where I also suggest to avoid any cables.
@davesradiorepairs63444 жыл бұрын
HI Andreas, I work for a major Wifi Manufacturer, and in order to do Mesh WiFi at greater distanced, you need to increase the "Acknowledgment Timer" timeout value. This is necessary due to the increased distance, causing increased propagation delays in the round-trip "packet send and acknowledge" sequences.. So, you MUST increase the timeout delay for the Acknowledgement Timer on the receiver side, (he must reply with an acknowledgement) in increasing increments per kilometre of distance from the peer device.. Since both peer devices send acknowledgements of received packets, then the timeout on BOTH side must be retarded as well, equally..
@AndreasSpiess4 жыл бұрын
Thank you for your tip! I will try it next time...
@illusivec8 жыл бұрын
Very good test. I think putting ESPs right on top of metal fence would reduce their range significantly tho. As a multirotor flyer, I've learned after many crashes, that one should not get close to big metal objects while using any wireless band. Another thing is, I'd bet that if you were to use 7-8dbi patch antennas instead of the crappy ducks, on both ends you can easily reach half a kilometer.
@AndreasSpiess8 жыл бұрын
+flanker I think, I should have a little more distance to the steel fence for the board. For the antenna, I think, it was not so important. But obviously, I did not look too much to that aspect and will do this in a later video. I already have some material coming (antennas, etc.) and I will try tu use also antennas with gain.
@illusivec8 жыл бұрын
Andreas Spiess I'd like to see that. Thanks.
@xpresa12008 жыл бұрын
agree with you flanker , and test range with iPad ? really? omg . iPad antenna ?
@jotchava8 жыл бұрын
I didn't know about the bomb shelter thing..
@AndreasSpiess8 жыл бұрын
This is so special I thougt, I mention it in my video...
@underwoodblog8 жыл бұрын
me neither
@brainfornothing4 жыл бұрын
Neither me ! Thanks !
@TechNed5 жыл бұрын
Hello. Thank you for this interesting video. Having survived the eighties (including some time as an RF tech), I think the bomb shelter policy is very wise. I often wonder about antenna efficiency and what difference a ground plane makes. I dismantled a WiFi antenna of similar appearance to the one in your test only to discover it was a straight length of wire, not dissimilar to the old quarter wave whip used on car roofs, etc (no base loading or such). They require the roof as a ground plane as you would know. There were base-loaded "ground-plane independent" antennae for use where truckers had non-conducting fibre-glass canopies or drivers who don't like holes being drilled in the centre of their roof so choose to gutter-mount. As far as I was aware, if they simply gutter-mounted a ground-plane dependent quarter-wave whip antenna base, it would propagate much more favourably in directions across the roof rather than omnidirectionally. If you mounted your SMA base on a metallic plate, I'm wondering if that might give different results..
@AndreasSpiess5 жыл бұрын
In the meantime I made a few videos about antennas, mainly under the topic LoRa, if you are interested. There you also see the influence of ground.
@TechNed5 жыл бұрын
Thanks. I've only just discovered your channel and got here by searching "esp8266" - I've been having hours of fun with those things..
@AndreasSpiess5 жыл бұрын
There are quite a few videos on 8266 as well as on the newer ESP32 on this channel ;-) Tomorrow the next one.
@BGLENN-dp4tx6 жыл бұрын
Very good video!! So, just to clarify the information regarding the sex of the connector being FCC-legislated due to some "fear of...radio amateur operators" , it should be pointed out that the changes to connectors is to establish a new industry standard convention for the purposes of recognition/compliance. After all, any technician wanting to work around connection issues certainly can do so if desired. But, generally speaking, technicians and engineers who might not be current or up-to-date about the fact that "other regulations apply", and who suddenly encounter connector reversal would certainly be asking the obvious: "Why?". But for the non-compliant-minded user, unique connector scenarios provide an immediate response by manufacturers to produce "adapters" Thus, anyone can simply subvert the sex change by using an adapter or even add a 'pigtail' if they so desired. The truth is that changing the connector doesn't accomplish any sort of deterent so much as it is there as a 'reminder' to the technical person (or not-so-technical person perhaps) that a special case exists. It is a further truth that connector variations (as with the SMA reverse sex variation) identify advancing technologies / units which fall under regulatory restrictions or operation apart from similar components commonly used heretofore (education lags production, as they say). We simply needed an obvious method of identification. Interestingly, these 'different' SMA connectors a but a small part of that convention. We have a multitude of various connectors with obtuse fittings including BNCs. Connector conventions were modified for this purpose long before network hardware was even a glint in the eyes of father WiFi. In closing, I think of this SMA sex reversal as a means to identify unique device operations to avoid bigger problems (like interference to other services). Historically, this need for tactile evidence of connection compatibility was never more vividly demonstrated than back in the day when pipes meant for carrying flamable natural gas were directly threadable to lines laid to carry water. The results were devastating. This would never have happened had the threads not matched. Be alert. Be safe. Be professional.
@AndreasSpiess6 жыл бұрын
For me these RP connectors are not necessary and useless. I mark all of them with a red point and also all needed adaptors.
@elpechos6 жыл бұрын
The technical audience had already decided on a connector -- "SMA". There were no technical need for two competing standards that do the same thing. Your water/gas analogy also makes no sense, because there's no danger in using SMA OR RP-SMA for what its designed for -- as an RF connector, they both do exactly the same thing, interface to the same equipment, and carry the same stuff. One is just more annoying. A better analogy would be two competing gas connectors, one of which is intended to stop you from frying eggs on a camp-stove, you can only attach water boiling equipment without an RP-Camp-Stove adapter. As for standards compliance -- many technical people will be licences to use higher power in 2.4ghz, anyhow (Eg, amateur radio licences, commercial licence). And these licenced people have to go through the trouble RP_SMA causes for no reason. Besides -- the fact RP-SMA was created to annoy consumers is clearly and nothing to do with 'assisting technical personnel' is clearly documented en.wikipedia.org/wiki/SMA_connector#Reverse_polarity
@BGLENN-dp4tx6 жыл бұрын
Thank you. I agree. Further support that the premise stated in the video that " the sex of the connector being FCC-legislated (due to some "fear of...radio amateur operators)", is unsupported by the facts. I learned some interesting facts from your reply. Much appreciated.
@TheBadNexus8 жыл бұрын
As far as I know. To get an wifi connection for places like at the back of your house, you could use something like a reflektor to reflect the signal to the backside. As far as I remember about more than 90% of the wireless signals inside an appartment arrive by refelction. I read this a while ago in a book called "WirelessLANs" from Joerg Rech. May be a interestin information.
@AndreasSpiess8 жыл бұрын
You are absolutely right. This is not only true for Wi-Fi signals. As Ham radio operators we e.g. use reflections of HF signals in the stratosphere to communicate worldwide.
@jamesgoacher16064 жыл бұрын
Purely for interest sake. I attended a meeting of Radio Amateurs the other day discussing the set up of a 2.4GHz local area network for Emergency communications purposes. This is within our allowed Band Plan. There is a group who have such a thing communicating across the Firth of Forth just north of Edinbough and we discussed being able to apply 400W (Radio Amateur maximum in the UK) against an annoying neighbour of one of the group, humourously of course (I think). We were expecting to get 5-10 km with about 3-5W amplifier and also an omni-version of similar expectation. This was based upon what had already been acheived by others.
@AndreasSpiess4 жыл бұрын
I know of those networks. There are quite a few around the globe. Mostly in metropolitan areas. But I did not know you have one in Scotland
@jamesgoacher16064 жыл бұрын
@@AndreasSpiess It is not a permanent net it is for use in and Emergency (RAYNET - Radio Amateurs Emergency Network) and this is a way of training for the set-up in the field in the case of necessity. Ease of deployment for instance and kit. At microwave frequencies the losses in the transmission line are enormous so transmitter at the antenna and remote control, it could be some metres up a pole.
@Spacedog493 жыл бұрын
Testing my ESP-12E with an ESP-01, I could communicate around 300 meters "Line of Sight". Switching to my Android phone and pad the range dropped to 50-60 meters. The phone and pad were more than 8 years old.
@AndreasSpiess3 жыл бұрын
Thank you for sharing your test results!
@blitzsss8 жыл бұрын
Hi Andreas, really enjoying your videos, i'm a novice and you are doing a great job of explaining these things in ways I can understand - thank you :) Just wanted to make a quick comment, I believe the ESP-12E is actually the newer ESP-12F the difference in the PCB antenna is very obvious if you look it up :)
@AndreasSpiess8 жыл бұрын
+blitzsss Thank you. You are a good observer! Until your comment I did not know that there is a difference beteween ESP-12E and -F. But you are right, they have at least a different antennas. Do you know, if they have other differencies? One is also marked Wemos, the others are marked Ai-Thinker. And I opened two modules for another project and discovered, that they had differen layout and also different flash chips. For me, as long as they behave similar, I treat them as the same. If not, we have at least a possible root cause for different behavior.
@blitzsss8 жыл бұрын
+Andreas Spiess Hello, sorry I do not know if there are any other differences but you might find this useful if you haven't already come across it. docs.google.com/document/d/1B06YzToSKxJ-tA1-AaTqacpzbxyexaV7Ick-ZtmvQj8/edit
@AndreasSpiess8 жыл бұрын
+blitzsss Thanks for the link. I did not know this document.
@chuckjordan64556 жыл бұрын
what I would like to know is if you connected a really good GROUND wire to a high quality ground, and if you also possibly added a choke to the ground so that no spikes can make it up to the ESP8266, would this improve range. Radio requires that duality of sky and ground. If you look into the Tate Ambient Power module circuit, you will see that it must be grounded for best effect. The pickup of RF and conversion to power works WAY better with ground. Similarly, transmitting would probably be boosted if you had good grounds on both sides.
@AndreasSpiess6 жыл бұрын
Most of these devices are battery operated and therefore not connected to ground. The antenna has to be optimized to deal with this fact, like in Smartphones for example.
@chuckjordan64556 жыл бұрын
it might be worth experimenting. how much of the signal is attenuated because of a lack of connection to earth ground?
@Konst82 Жыл бұрын
Неплохой результат для прямой видимости :)
@AndreasSpiess Жыл бұрын
I agree!
@Spentamanyu8 жыл бұрын
Nice analogy between 2.2GHz and light beams
@AndreasSpiess8 жыл бұрын
+Spentamanyu Thanks!
@PolakeXD6 жыл бұрын
I own a DSTIKE WiFi Deauther OLED V1.5S Board and it has the ESP8266 chip and it was able to detect my FritzBox from about 350meter (Fritzbox and Deauther Outdoor) but if I put the FritzBox indoor and I was outdoor then the range was 140meter. The connectivity can be always different because of environment. For example last month I lived at Frankfurt am Main and there I wasn't able to get my signal even from in front of the parking lot which was directly in front of the house.
@candrasniper34048 ай бұрын
I have already assumed that the signal transmission related to the temperature too. And I see your comment. Thanks.
@rbmfreigeistvorsorger6202 Жыл бұрын
max. 120m/393ft in open terrain = ESP8266 12E 12E at 802.11b TX -20dBm I use the beacon frame for TX and scan networks for RX between the devices. The maximum distance without an external antenna is 120m or 393ft in open terrain. I try to build a mesh network of wifi hotspots, where each node provide a access point and webserver to smartphones / wifi clients. All neighbouring nodes exchange data with each other to increase the range between the smartphones. There is no master node and each node acts as an independent gateway as in APRS routing.
@AndreasSpiess Жыл бұрын
Maybe you google AREDN. This is a mesh network of routers and access points, too.
@srotogargees17915 жыл бұрын
...you should try connecting powerline networking from your router to your basement or anywhere ....also try testing it from 10km away to your home router
@AndreasSpiess5 жыл бұрын
I do not see a relationship between powerline and the range of WiFi
@srotogargees17915 жыл бұрын
@@AndreasSpiess ...ok i agree that was stupid...but think ..let say if i could broadcast the same lossless AP of my router on the other end via exsisting powerline transmission 10km away with similar hz (repeater) , where it connects to the esp8266/32 does it not add to the range of my WIFI
@frutt5k3 жыл бұрын
I did some tests with WLAN stations. Some could KEEP a link intact upto 200 meters. Yet, when at 200 meters, and you would disconnect, you could not reconnect at that distance. Disconnect/reconnect would only work upto someting like 120 meters.
@AndreasSpiess3 жыл бұрын
Good Information. Thank you.
@sonofusion8 жыл бұрын
if data rate is not important, perhaps you can try setting it to lower speed 802.11b, from the datasheet, it seems to transmit higher power and also it has better sensitivity with 802.11b. Tx power 802.11 b: +20 dBm 802.11 g: +17 dBm 802.11 n: +14 dBm Rx Sensitivity 802.11 b: -91 dbm (11 Mbps) 802.11 g: -75 dbm (54 Mbps) 802.11 n: -72 dbm (MCS7) doc.switch-science.com/datasheets/0b-esp8266_system_description_en_v1.4.pdf
@AndreasSpiess8 жыл бұрын
+YewMing Chen You are right. I did not look at the speed of the transmission during my tests. I anyway plan to play again with the chips ans some antennas in the future. So, I will also look at the speed then.
@norm11248 жыл бұрын
Gratulation für die bald 1'000 Abonnenten.
@AndreasSpiess8 жыл бұрын
+norm1124 Du bist ja offiziell mein erster Subscriber, der noch dabei ist (laut KZbin Auswertung)! Es freut mich auch, denn in so einem Video steckt ja viel Arbeit. Deshalb ist es schön, wenn es auch genutzt wird.
@norm11248 жыл бұрын
+Andreas Spiess Echt? I feel very honored Sir.
@AndreasSpiess8 жыл бұрын
+norm1124 Das kannst Du Dir zuschreiben. Ich habe da ja nichts beigetragen...
@jonpaul49355 жыл бұрын
A wifi connection is only as strong as it's weakest link ... this could well be the Ipad and thus you really should have used 2 identical esp8266's communicating with each other.
@grasi58464 жыл бұрын
good point
@hesspet7 жыл бұрын
You get nearly the same results I could get the with ESP-07. I've mounted the setup on a autonomous rover running on the ground. I can get a stable connection aprox 120-130 m on the ground the antenna mounted aprox. 40 cm above the rover, but only when I have a direct view to the rover. If the rover moves behind a big tree or behind a wall the signal is lost at this range. Best result with a Wifi Repeater mounted on a pole 2m over the ground was aprox. 200 m. (Must stop the test, cause the rover tends to drive in a small river...) but at this time the signal was not very strong, but OK with no packet losses via UDP. This is not a theoretical value. It's a real working scenario. It looks like that the results are a little bit better if I stay away from the town aprox. 1km. There are no private WLANS anymore. The results tends to be a little bit better. Some tests must be done in the outback far away from civilisation....
@AndreasSpiess7 жыл бұрын
Thank you for your feedback. It is always good, if others repeat tests to approve the results of find different ones. This is, how science moves on...
@nissimzur18 жыл бұрын
Dear Mr. Andreas Spiess Thank you for sharing experience on ESP8266. As expert on RF design I like to help you to improve designs and demos as you presents. You can call me any time my Skype nissim.test see me also at www.TelnT.com nissim@TelnT.com Regarding the range test experiment you make: As you can see on the <a href="#" class="seekto" data-time="108">1:48</a> minutes on the right top side of the red circular there is capacitor. This capacitor must be removed if you like to use the U_FL connector. See this capacitor at goo.gl/cYaZHF layout. The reason is simple: the maximum RF distance is based on good impedance matching the Microstrip (wire to antenna on PCB) to antenna must be 50 ohm. That Microstrip now is 50 ohm with the ceramic antenna. The U_FL connector is also 50 ohm without external antenna. So all Microstrip is 50 ohm But: if you connect external antenna to U_FL without remove the capacitor you get two antennas parallel to each other (the Microstrip “see” 25 ohm) and the Microstrip has to drive 25 ohm. ESP8266 see 50 ohm that end with 25 ohm. That is very bad. Just 33 % or less of the RF energy will be RF broadcast. Moreover will be a standing and return waves on the Microstrip that will reduce the RF energy out even more. Return waves will warm the ESP8266 and can destroy its final PA RF stage. Two antennas may effect and cancelled each other if they are in a distance of multiply of ¼ wave length (30mm). Placing the antenna on roof extend the distance since distance from ground do that. But making the antenna on the long metal fence on the roof may reduce or increase the distance. The long metal fence act as resonance antenna two. Since ESP8266 can work in several Wi-Fi mode. If you lock it to ST B mode, you will get +19.5dBm output power in 802.11b mode. See wiki.iteadstudio.com/ESP8266_Serial_WIFI_Module I do free Skype (nissim.test) help as part of my contribution to the society. You and other viewers are welcome to call. Dr. Nissim Zur (nissim@elinistech.com)
@AndreasSpiess8 жыл бұрын
+Nissim Zur Thank you very much for your valuable comment. I will investigate later into it. It needs some work... I anyway plan to dig more into this topic during summer. We can keep the contact.
@AndreasSpiess7 жыл бұрын
1. for the ESP-07 you are right. 2. Because the ESP-12 has no antenna connector, you cannot attach a antenna (at least, if you are not a well trained person with lots of mechanical skill. This is why I use a ESP-07 if I need an antenna (or the Wemos Mini Pro)
@chewysplace35427 жыл бұрын
same thing on the wemos d1 mini pro..u need to unsolder and rotate the pcb antenna's 0 ohm capacitor to the disconnected ext ant port on board PCB and resolder(the silver blob in front of the ext antenna not the antenna itself)...so if u look at it is a bridge... wherever it is soldered ...one or the other..actually is easier on the 07 than the Mini Pro as you only have to remove the capacitor on the 07...on the Mini Pro you need to resolder to the ext antenna capacitor to bridge it..if u mess up too just solder a very small piece of copper wire, like inside of coax, works fine....but both the 07 and Mini Pro you are loosing massive gain...so look at it like your antenna is loosing gain from having an unneeded protruding antenna that is not the right size anymore throwing it way off calibration...
@ko5t1k4 жыл бұрын
Thank's for overview!
@AndreasSpiess4 жыл бұрын
You are welcome!
@kamit015 жыл бұрын
Thanks for Your Project, I also tested my NodeMCU and built a car that runs from browser and Wifi. First it was running only short range like about 100m. But when I removed my NODEMCU from toy car and tested it ranged 310 m. :) Your tutorials are very good and informative. I am a professional Civil Engineer :) learnt Python and learning Arduino now.
@AndreasSpiess5 жыл бұрын
Thanks for your feedback. More than 300 m is very good :-)
@RafaelBSFerreira5 жыл бұрын
Thanks for sharing. Nice video.
@AndreasSpiess5 жыл бұрын
You are welcome!
@zazugee4 жыл бұрын
about line of sight, i have a D-Link wifi router inside the house, and my phone can still connect to wifi up to 50m from outside i also my laptop can detect from rooftop and ESSID from 200m away, so it seems possible you can transfer data at a low bitrate at those long distances
@AndreasSpiess4 жыл бұрын
Thank you for your feedback!
@mtt82448 жыл бұрын
Found your video on research for external antenna use of esp07. As far as i know you have to disconnect the ceramic antenna, just remove the 0ohm resistor between u/Fl and power led. @<a href="#" class="seekto" data-time="107">1:47</a> i can see the resistor is still there, did you desolder it?
@AndreasSpiess8 жыл бұрын
When I did this video, I did not know, but a viewer wrote it in the comments. I have to try this in a future video.
@muppetpaster5 жыл бұрын
yep you have to remove it
@GeorgeOu7 жыл бұрын
You need to have the ESP-12 in the vertical orientation to get maximum range. This matches the vertical polarity of a normal whip antenna in the vertical orientation.
@AndreasSpiess7 жыл бұрын
I agree with you that polarization makes a difference, But if one station is movable, it is not easy to align polarity. I used a IPad and I do not know the polarization of this device. And in addition, I moved it all the time. Many of my applications are similar and I cannot adjust polarization on both sides. So, I think, we have to live with what we get without adjusted polarization.
@GeorgeOu7 жыл бұрын
Is it possible to have a second Rainsun chip antenna rotated 90-deg in place of the u.FL connector? That way both polarities are covered on-chip.
@AndreasSpiess7 жыл бұрын
This is not easy because if you put them in parallel, then you only have 25 Ohm which would be a complete mismatch. In series, you would get 100 Ohm. So, you would need a imedance converter, which is not easy to be built on 2.4 GHz. BTW: The best channel about 2.4GHz antennas is: kzbin.info/door/HqwzhcFOsoFFh33Uy8rAgQ
@GeorgeOu7 жыл бұрын
So totally impractical to have 2 chip antennas on one PCB? How does the ESP-7 support external and internal antenna concurrently? Or does the ESP-7 disable internal antenna when you connect external?
@AndreasSpiess7 жыл бұрын
+George Ou You have to unsolder a component, if you want to use the external antenna. But I didn't know this when I made the video. A viewer told me
@KucharJosef8 жыл бұрын
He was using wifi router as AP, and ESP8266 as client. His second test with 4 km success is becose he used directional antenna
@AndreasSpiess8 жыл бұрын
I think, he wanted to prove what these little modules are able to do. So, He tried to find a maximum.
@KucharJosef8 жыл бұрын
I think he used udp ping oneway
@hadestech81473 жыл бұрын
Andreas, Thanks...
@AndreasSpiess3 жыл бұрын
You are welcome!
@slicedpage5 жыл бұрын
thank you. I am about to start a project with the 8266 so this information helps me a lot. And capability is pronounced K-APE as in Batman's cape. :)respectfully
@AndreasSpiess5 жыл бұрын
Thanks for the tip. I hope I will not forget it next time.
@yashvachhani1735 жыл бұрын
Can you tell me how you connect esp8266 with antenna, if possible please give me the diagram
@AndreasSpiess5 жыл бұрын
Easy: Buy a module with an antenna connector as I did in this video.
@half4team8 жыл бұрын
I think you have to considder de 'used' powersupply. the range will improve with a supply that can deliver more current.
@AndreasSpiess8 жыл бұрын
+half4team I used a power bank. I will do the test once again and also use different configurations (antennas, places).
@underwoodblog8 жыл бұрын
A good power supply is very important. I've had lots of trouble with my ESP-01 that I have connected to my doorbell. Like connection losts and freezes. After I've added a 0,1F goldcap capacitor it works without errors. I think I've readed somewhere, that the ESP can use up to 800mA on a very short burst.
@AndreasSpiess8 жыл бұрын
If you look at some of my newer videos you see, that I have gone the same way... Just bigger capacitors.
@pino_de_vogel4 жыл бұрын
Nice explanation on showing why consumers are always smarter then suits in governmet. forbid something or make something impossible and a solution is made in days.
@AndreasSpiess4 жыл бұрын
On the other hand I am quite happy that we have laws. I would not have survived long in the Wild West ;-)
@user-ry4kw3yt3v2 жыл бұрын
Thank you for being a follower in Iraq
@AndreasSpiess2 жыл бұрын
:-)
@dhruvenvaghela80515 жыл бұрын
Can you give the exact diagram of connection with node mcu and wifi antenna
@AndreasSpiess5 жыл бұрын
Buy a module with an antenna connector as I did in this video.
@Cicuiranu7 жыл бұрын
hello, the antenna is not an ILA but an IFA. I have skills for antennas but not for that kind of circuits. I'm learning. Thank you 73.
@AndreasSpiess7 жыл бұрын
:-)
@Bluesparker2 жыл бұрын
LOL when my workbench gets crowded like that, I skip mental frames and make audio hash noise that interferes with those around me. That one above is not badly crowded YET I'll bet.
@AndreasSpiess2 жыл бұрын
:-))
@Bluesparker2 жыл бұрын
I am not an antenna specialist, that science is as tricky as making a chunk of hamburger grow the way one wants it to. But I do wonder if the metal fence helps or attenuates the signal. Seems that a ground stub equal in length with the radiating element , a dipole , would give better gain. The problem is the unbalanced transmission cable. So that brings the complication of getting the signal to the antenna through a balanced cable, doesn’t it .
@danielszekely51974 жыл бұрын
a normal usb wifi adapter of 3000 mw with dual antena of +5db can reach ~1km range in straight line, i tested it switch its antenas with +8db and reach ~1.5km 150m i can reach with my phone :))
@AndreasSpiess4 жыл бұрын
Thank you for sharing your experience. I would never cover such devices publicly because it is forbidden to use them where I live :-(
@danielszekely51974 жыл бұрын
@@AndreasSpiess no way, but you can buy them from any store : tl wn8200nd www.ebay.co.uk/itm/TP-Link-TL-WN8200ND-Wireless-USB-Adaptor-Dongle-300Mbps-Tested-Warranty-B/173990654942?hash=item2882a6b3de:g:LGEAAOSwv7BdSvlY even this one can reach at least 500 meters www.tp-link.com/us/home-networking/usb-adapter/tl-wn722n/
@modelmanmark4 жыл бұрын
Not a fair comparison when using 3 watts compared to the legal 0.1 watt here in the UK.
@guywhoknows3 жыл бұрын
@@modelmanmark that only came Into effect in 2006, this is due to the issue of everyone having WiFi in home and the noise it created. The "signal leaks" to other AP's caused many connection issues and poor transfer, so they made a limit, a transmit limit. 5ghz band a is .2watt, band b 1w and band c 4w. (Its also licenced). Back when testing, we used the max legal transmit power, but we had split send and receive antenna. The dB limit is between antenna and power, so care had to be taken.. You could only have a 2-4db transmission antenna. A receive on the other hand was and is not (haven't checked) limited. So you put up a big ear, 30db and your can hear the signal. But most protocols don't work as you can't reply (CRC) to standard antenna, but two separate send and receive can. By listening and not shouting ;) Where we did the testing, we could get a weak signal at 35km. But practical was 8. And of course weather, Los, and topology of the grouns all made a big difference. And was in our favour.
@CarsonNiepper71186 жыл бұрын
Andreas, thank you very much for great work. I learned a lot from your videos. I made range test for Wemos D1 mini (with PCB antenna) but with ESP-NOW protocol .(Thank you again!) Robust connection distance is about 400 meters but I believe that it can go further. I will check. Receiver was 16th floor of a building and transmitter was at ground level. After your test, my test results seems to me a little bit suspicious.))) Let's say being in 16th floor can effect the range but what about using ESP-NOW protocol? Can it somehow extend distance? Thank you. Regards
@AndreasSpiess6 жыл бұрын
I think the Ipad was not the best choice. 400 or more meters seem to be ok for me.
@larsniklassonhede37985 жыл бұрын
Thanks for the truth. I have the same problem about the distance. I wanted to have 4 units of ESP8266-Wifi moduls inside my house in different possitions. I have a house made of wood so I thought that should not be any problem . But it seems the modules have to see each other to be connect. I thougt they should be communicating through the router and not direct. I am very disappointed on these modules. I have only onboard antennas. The antennas on a mobile phone is not bigger so that should not be any problems. I like your accent.
@AndreasSpiess5 жыл бұрын
If you use them in the normal way they always connect to the Wi-Fi Hotspot you select in your sketch (SSID). I also would assume they should work in a wooden home. Did you make tests were they worked and where not?
@harshsutariya86295 жыл бұрын
Can i get the diagram, how you connect node mcu with antenna
@AndreasSpiess5 жыл бұрын
Just buy a module with an antenna connector as I did in this video.
@mokoyusha76947 жыл бұрын
very descriptive, thumbs up!
@AndreasSpiess7 жыл бұрын
+Dian Dixon Thanks!
@HamedAdefuwa3 жыл бұрын
I'm having this problem as well, 15 metres through two walls not working :(
@AndreasSpiess3 жыл бұрын
Walls are never good for Wireless systems :-(
@MilanKarakas8 жыл бұрын
Remember that smartphones, ipads and tablets has really bad antennas inside, so range is short. If you can extend antenna from your tablet, you may expect at least 1 km range.
@AndreasSpiess8 жыл бұрын
I will try different antennas later this year
@MilanKarakas8 жыл бұрын
Thanks. Now I am subscribed to your channel and will follow your experiments.
@AndreasSpiess8 жыл бұрын
Thanks!
@witoldgizewski64574 жыл бұрын
Hello, Please show how to connect an external antenna wire to a board with no antenna socket. How to solder to the onboard esp8266 antenna path, where the cable shield and its middle wire? Do I need to cut path and where to do it? Thx
@AndreasSpiess4 жыл бұрын
I do not suggest doing that so I will not show it.
@signulltech2 жыл бұрын
Thanks, now means the wemos d1 mini (PCB Antenna) is about 90 meters range?!
@AndreasSpiess2 жыл бұрын
You have to try it. It also depends on the receiving station. It should be possible with line of sight between the two devices.
@Graham19048 жыл бұрын
Out of interest the little coaxial connector you referred to is a U.Fl
@AndreasSpiess8 жыл бұрын
+Graham Gillett Thank you for this info. So, I learned something this evening! They are really very small and have to be fabricated very precise, I assume. I think I first saw one of them when I changed the battery in my Iphone, but never googled its name... For my eyes and my hands, SMA is alreay small enough!
@brainfornothing4 жыл бұрын
Thanks for sharing !
@AndreasSpiess4 жыл бұрын
:-)
@d-popov4 жыл бұрын
Shouldn't you set up a connection between 2 ESPs? Now you are also measuring iPad's connect capabilities.
@AndreasSpiess4 жыл бұрын
You are right.
@yelectric18933 жыл бұрын
Hmm this is very promising. Even though it’s not outstanding per say, could make a pretty cheap RC plane with WIFI links
@AndreasSpiess3 жыл бұрын
Wi-Fi is not made for a long range, more for big capacity. That is why it is not often used for RC planes.
@yelectric18933 жыл бұрын
@@AndreasSpiess I see. Maybe there is a niche for it though. Thank you for your response and making these videos by the way, they are so interesting and fun.
@youdontwantthesecrumbs39964 жыл бұрын
Great video, I have seen 2.4Ghz are incredibly sensitive to walls when it comes to range and reaching your 8266 chip. Mine came with a 8bd small antenna, and although it gave me about a %10 increase in strength and range, its still small. I have heard you can make a large antenna out of a can, "Cantenna" ever heard of this? Would be a good video and possibly a massive range.
@AndreasSpiess4 жыл бұрын
I heard of the cantennas. You find good videos on how to build them. Not on this channel.
@eliasjoserodriguez51602 жыл бұрын
@@AndreasSpiess I habe a question for you how did you do the esp-07 a access point you need to programed it or it's already progamed for use it like a access point? (I want to use it like a wifi repeater why I habe a long range antenna and I want to use it like a repeater)
@AndreasSpiess2 жыл бұрын
@@eliasjoserodriguez5160 The ESPs usually are not programmed
@eliasjoserodriguez51602 жыл бұрын
@@AndreasSpiess and how I can program the esp-07?
@AndreasSpiess2 жыл бұрын
@@eliasjoserodriguez5160 You find a lot of videos about that matter.
@___xyz___7 жыл бұрын
the swiss accent reminds me of the swedish accent. don't worry, that's a compliment
@AndreasSpiess7 жыл бұрын
Thanks!
@crjdreams19914 жыл бұрын
Esp 07S should be always connected to device like laptop? Or It can transfer the Wi-Fi to longer distances same as repeater does.
@N.g.Chanal Жыл бұрын
sir please check esp8266 to esp 8266 direct comunication rang test. on this setting tx 25dbm rx-97dbm .
@AndreasSpiess Жыл бұрын
So far I have no such plans :-(
@nahrings Жыл бұрын
Hallo danke für das Video. Ergänzen möchte ich wissen warum bei dem Test nicht gleich wie auf dem esp-07 Board befindliche Rainsun mitgetestet wurde? Diese Antennen sind noch ein Stückchen kleiner als die auf der Leiterplatine aufgedruckte Schlangenlinie. Wenn du dich etwas mit Antennen auskennst fragst du natürlich auch immer nach dem Strahlungsdiagramm, denn das ist dasjenige was den Antennengewinn ausmacht. Daraus resultieren die größten Vorteile eines Antennenwechsels. Da ich selbst nun auch kein großer Fachmann bei diesen kleinen Wellen bin hätte mich noch interessiert in welche Richtung die Leiterplatinenantenne und diese aufgelötete Rainsun Antenne strahlt. Es wäre schön wenn ich dazu Informationen hier bekommen könnte.
@AndreasSpiess Жыл бұрын
Solche kleinen Antennen habe keine starke Richtwirkung (auch wenn das auf Diagrammen so aussieht)
@gayathribalamurugan8919 Жыл бұрын
Greetings, Sir, for 2.4GHz you r using esp 8266... bt please suggest some module to test the 3.3GHz antenna (external antenna)
@AndreasSpiess Жыл бұрын
3.3GHz is not a legal band to use without a license where I live :-(
@Jishan0074 жыл бұрын
In my test i was able to connect only 28m ...is something wrong with my board??
@AndreasSpiess4 жыл бұрын
I do not know.
@lakhveerchahal4 жыл бұрын
Thank you, that was very helpful. Just a quick question. Can we use a Zigbee module also for capturing the Wi-Fi signals coming from an access point? Thank you.
@AndreasSpiess4 жыл бұрын
No. They are different
@lmarloe6 жыл бұрын
What about Impedance matching ? First in specs was 50 Ohm, but then they changed it to 39+j6. I wonder how this affects when choosing an antenna
@AndreasSpiess6 жыл бұрын
I did not look at this matter since then. So I do not know. Watching my newer videos you see that antenna matching seems to be important...
@tahayt61423 жыл бұрын
Hi is there not an attachment that u can put on the nodemcu esp8266 pins to extend the range(antenna board maby??)
@AndreasSpiess3 жыл бұрын
Some boards have antenna connectors were you can connect your own antenna.
@jovanimann59097 жыл бұрын
gotta have ESP8266 very interesting
@AndreasSpiess7 жыл бұрын
+Jovani Mann I use them for many purposes. Maybe you watch some of my other videos for ideas?
@Stav_Bodik8 жыл бұрын
It will be more interesting how far can 2 esps talk together , so the distance wont depend on device used to connect to the esp .
@AndreasSpiess8 жыл бұрын
You are right. This the topic of a future video
@Stav_Bodik8 жыл бұрын
Thanks you for doing amazing job!
@AndreasSpiess8 жыл бұрын
Yeah, I know these videos. Great channel!
@mrblason8 жыл бұрын
I have tested this case inside my house... two ESPs, one send UDP packets ,the other receives. I confirm that the range is 16m/20m with an RSSI on sender of -85/-90dB with a percentage close to zero of lost packets. The same result if the two ESPs are on different floors. I have not tried it outdoors yet.
@AndreasSpiess8 жыл бұрын
Thanks for the info!
@Mikhail-Milkhail4 жыл бұрын
Спасибо!
@AndreasSpiess4 жыл бұрын
Пожалуйста. Не за что
@FelixCrazzolara4 жыл бұрын
Hi Andreas what would you argue is the effective maximum range for the ESP-12E in a direct line-of-sight scenario? With effective meaning that you connecting to the ESP and/or loading the webpage does not take an excessive amount of time or numbers tries to connect respectively.
@AndreasSpiess4 жыл бұрын
Maybe a few hundred meters. I never tried it
@avejst7 жыл бұрын
Thanks for sharing :-), Good insigth
@AndreasSpiess7 жыл бұрын
You are welcome!
@javierunamuno67867 жыл бұрын
Since I've seen this video some three months ago, I kept wondering what are your options if the Swiss government dictates a mandatory nuclear bombing drill? Take all your stuff to the garden, so the neighbours can come in? Invite the neigbours to a tea party at your house during the drill? it will cost you a lot less! Will they accept?, or are they, in general, too law-abiding citizens? Thanks for the videos, and, the Swiss humour!
@AndreasSpiess7 жыл бұрын
And in addition, we have now to deal with a new situation in the US. We always felt protected by their Atomic Bombs...
@d.j.peters8 жыл бұрын
Looks like something is wrong in your test setup how much current your power supply supports ? I get ~3,000 meters with external antenna and ~800 meters with a PCB antenna. DJ
@AndreasSpiess8 жыл бұрын
+DJLinux007 Very interesting result. I do not think, it is the power supply. What was your receiving device (I used an Ipad)?
@d.j.peters8 жыл бұрын
+Andreas Spiess the receiver are a second ESP8266 with PCB antenna. Your results are really bad compared to a cheap 2.4G nRF24L01P module also. Something must be wrong any high power cables in the near air or power cables from a train ? May be you should repeat your test on a totaly different place. DJ
@AndreasSpiess8 жыл бұрын
Thanks fir the info. I keep it on my list. Also the comparison with the NRF24L01
@Geza_Molnar_5 жыл бұрын
@@AndreasSpiess Hi, maybe the lots of amount and wide surface of the iron fence was the reason for the (possible) weak result. They say, that's one of the main reasons why wifi and bt does not work well in factories. I'm curious.
@LouiesLog5 жыл бұрын
Impressive!
@AndreasSpiess5 жыл бұрын
Thank you!
@awmzy88972 жыл бұрын
so any form of the esp8266 with no attachments is 90 metres, correct?
@AndreasSpiess2 жыл бұрын
You have to try in your environment.
@BenjaminHari Жыл бұрын
No freaking way that other guy had few kilometres reach without some extreme power delivered to the chip....your results match exactly what on average range of 2,4GHz AP are on average. I'm actually surprised that without Antenna it can reach even that far, then again it's outside test without any walls lol.
@AndreasSpiess Жыл бұрын
Indeed, outside it is easier to reach a longer range...
@HouseMusicLover0017 жыл бұрын
I bought one esp8266 and burned its memory because I think I have a faulty USB to TTL adapter. I tried lighting an LED with the adapter and it burned in a few seconds, even though the adapter is supposed to give out 3.3V. I'll buy another memory chip and hope that's the only thing I burned off on the esp
@AndreasSpiess7 жыл бұрын
Bad luck!
@timekeeperstv68737 ай бұрын
How did you connect the externel antenna to esp8266 using esp e07?
@AndreasSpiess7 ай бұрын
The ESP-07 has an antenna connector.
@NovaFragment7 жыл бұрын
Hey Andreas, was just wondering if i could do this with my ESP8266 board,the node MC board (www.penninkhof.com/wp-content/uploads/2015/08/113990105-11.jpg) This one Am i able to attach a antenna to it? i searched everywhere and can't find anything
@AndreasSpiess7 жыл бұрын
No, the ESP-12 boards have no antenna connectors
@DanniieLTorres7 жыл бұрын
I have the same question.. i was wondering if i could use the Pins to attach an antenna somehow but no luck
@AndreasSpiess7 жыл бұрын
These devices use extremely high frequencies and it is not easy to build a proper antenna without good equipment.
@zebrahuhn58998 жыл бұрын
Thanks for the test, Andreas! I would be interested, how far the ceramic antenna on the ESP-07 reaches compared to the PCB on the ESP-12E. And you said, the ESP-12E did not work behind the house. What about the ESP-07? (with or without external antenna)
@AndreasSpiess8 жыл бұрын
+Zebrahuhn I will anyway do a second test with new scenarios, especially I will replace the Ipad as a receiver, because other commenters wrote, that this might limit the reach. The ceramic antenna should have about the same performance because of its comparable size and no obvious directional effects.
@underwoodblog8 жыл бұрын
I think he is in the "shadow" of his house or some other possible effects. In some rare cases the signal could be to strong and distort the input of the receiver. Had this effect on a moded Linksys WRT54GL. Everything worked fine if I was 20m or more away but I lost signal when I'm between 0 and 3m.
@21geometrydash204 жыл бұрын
can the PCB antenna connect to the nodemcu esp8266 wifi board?
@AndreasSpiess4 жыл бұрын
Only if you have a antenna connetor
@serhiikuzmychov87847 жыл бұрын
thanks a lot!
@AndreasSpiess7 жыл бұрын
You are welcome!
@jwuethrich83857 жыл бұрын
grew up during that time. got ham ticket at 13... rpsmal always pissed me off as a kid and i never knew it was a mandate due to hams. Id like to see some documentation and may google it later. If i recall some 15 years after passing that test and 7 or not touching a ham radio.. ham operators in the us are explicitly allowed priority and higher power on 2.4ghz ism so it doesnt quite fit your story...then again...to quote peter griffen "its the fucking fcc"
@AndreasSpiess7 жыл бұрын
I do not know the US frequency bands, and I think, some bands were reserved for hams in the old days when nobody had the equipment for these high frequencies. Later, some of these bands were reduced and re-purposed to other usages.