Testing the FrSky R9 T-Antennas and explaining the coloured bands for different regions

[@stevefox3763]

an antenna being perfectly tuned will improve performance to a degree when talking long distance but the most critical reason for having an antenna tuned to the frequency is SWR, this stands for standing wave ratio. To simplify, the higher the swr the more transmission power that is reflected back at the output stage of the transmitter instead of being converted to radiated power out of the antenna, high swr will shorten the life of a transmitter and over a certain level, it will kill it very quickly. tolerances on antenna length at 868-915mhz are reasonable but at 5.8ghz, antennas need to be built to within a 10th of a mm else they will be wildly off frequency for example, if a 5.8ghz antenna is just 0.2mm too short it will be 100mhz too high and be on 5.9ghz and if its 0.2mm too long it will be tuned to 5.7ghz. yep, two tenths of a mm puts it out by 100 mhz and thats bad! in addition to this, the antenna consists of two main elements and both must be correct, not only can the antenna be off frequwncy it can be unbalanced too :/ so for this reason i dont recommend home build 5.8ghz antennas when down at 868mhz, you need to be a whole 8.5mm out on the length to get the same 100mhz off frequency as 0.2mm would at 5.8ghz, this is what i meant by the tollerance.

[@CurryKitten]

Thanks Steve, I'm certainly no expert in talking RF stuff (as you may have noticed) so that was a useful technical explanation

[@stevefox3763]

@@CurryKitten im not an expert but i run two way radios and so need to understand basic antenna construction and tuning which suddenly found a new use when i started flying fpv :) BTW, "the plenty of time to be dead later" at the beginning is hilarious and i cracked up ha ha

[@Steve-O_FPV]

Steve - You play Tekken?

[@danlatu209]

Are rx and tx antennas the same? I wanted to internally mount an r9m lite and tbs immortal t with ufl inside my radio.

[@blackmennewstyle]

I bought my FrSky T antennas while ago on Banggood and they all came without any colored bands, like i guessed at the time, they were like the TBS T antennas, tuned for both firmwares: FCC and LBT! Thanks for sharing and happy midweek :)

[@CurryKitten]

Out of interest, how long ago did you get yours. I haven't had my Super-8 that long, but there's been 2 more batches since. Really, though - how hard is it to have a web page explaining things to your customers !

[@blackmennewstyle]

@@CurryKitten Not so long time ago actually after checking my ordesr history on banggood, it was in late October. Well, when having the chance to live in an asian country close to China since many years now, you actually learn quite a lot about chinese culture. Customers service is China is culturally inexistant, it is something they just started to discover and apprehend few decades ago. Did you know by the way that Chinese people are very reluctant buy their own local products because when a product is designed for the local market even from foreign companies (like Apple for example), they reduce drastically the quality for the chinese market. It's cultural but so strange. Even international chinese companies like DJI for example are doing the same with their products. It's fascinating to discover all these cultural divergences and the more you learn about them and the more you understand many things we have seen during many years in the hobby with many products...

[@imager09tube]

How are Curry? Nice job man! Excellent effort! Marry Christmas to you and your family!

[@lostjohnny9000]

We tested all the R9 kit too using the R9M Lite with various receivers including the R9Slim with dual yellow band dipoles. Also tested with an ImmersionRC V2 RF meter. We still got inconsistant RSSI and low signal warnings until we tried a Mox antenna. The Super8 is certainly better than the rubber duck dipole but the Mox just works. £20 well spent.

[@CurryKitten]

Good to know - lots of people seem to like the mox

[@TakeItToTheGround]

I keep looking at how wet & muddy the field is and I think you should be testing with an RC boat.

[@CurryKitten]

Welcome to 8 months of the year for me - it's pretty important to be able to make a spot landing when it's that wet. I used to bring a chair with me, but after sitting on it for 10 minutes I'd find that the legs had sunk completely into the mud and I'd have to dig it out :D

[@DavidHanniganJr]

Anytime that you use hot glue and you want to get it off, and you don't want to run the risk of it pulling something off, just use rubbing alcohol. Or denatured alcohol. Works like a charm.

[@CurryKitten]

I've not heard of doing that - cheers, I'll give it a go next time

[@dj_dazzy]

@@CurryKitten it is called IPA, Isopropanol or Isopropyl Alcohol in the UK. Far better than Meths because it leaves no residue and can be used for a multitude of things including releasing hotsnot bonds.

[@sebastiansombra]

Thanks for the tests. You should also try with vertical orientation (both in TX and RX). I know it represents a challenge setting the antenna in the quad, but I’ve read in the forums that is the best option.

[@CurryKitten]

Vertical will work better for ultimate range, so if I get one of these in a wing I'll go vertical. It's just too much hassle for me in a quad

[@marcind4795]

Dear CurryKitten , thank you for your film and explanation about colors. Could you do a range test on Super-8+T? In my configuration on stock antennas with 25mW I am not able to reach 3km and in that case this entire R9 system does not make any sense for me.

[@CurryKitten]

By "Stock antenna" do you mean the rubber duck thing that R9 originally came with. I think you'd struggle to reach 1km on those. I'm afraid I just don't have the space to do that sort of range test - and I tend to use flex on r9 as I want it to ramp up the power if the signal strength is getting low. Any range test also depends on conditions, antenna placement, rf noise and altitude. There's no issues getting to 3km on a regular FrSky rx under the right conditions.

[@robrow]

Managed to get hold of a yellow banded Super 8 but trying it on the receiving end interestingly.

[@Clickbaiters]

Thanks for this follow up video!. I think I'll just stick to the TBS "T" antenna for the R9M lite module and the Frsky "T" antenna for the RX purely for ease of mounting.

[@jasondonavich2758]

Also the super 8 is definitely not a long range antenna. What I do to keep my ipex plug down is put a small piece of rubber over the top then heat shrink over that so it gives a bit more force on the connection. I've had them still pop off just using heat shrink.

[@pietroseven8228]

Yesterday and today lost signal r9mm ota, flywoo lr4 v2, 868MHz after 300m.

[@raabaman]

Excellent. Very timely video. I ordered both the super 8 and the dipole T antennas from HorusRC last night. They both required selecting EU or Non-EU. It will be interesting to see if they show up with any specific markings as you point out.

[@CurryKitten]

Yes, as if you read the spec under the product page they still talk about it having a peak gain at 900mhz and with a range of 860-930Mhz. They are probably just leaving the old spec sheet stuff in there from FrSky, but it doesn't really help alleviate the confusion :)

[@dan-erikwesterholm8572]

I just got a Super 8 with yellow band from Banggood

[@CurryKitten]

I saw they had an 868 spec listed, but the info on it was vague. I presume you ordered the 868 version ?

[@dan-erikwesterholm8572]

@@CurryKitten Yes I did but I was not sure if it matter and the information is a bit confusing at Banggood sometimes

[@CurryKitten]

Yes - I get the impression that retailers have the new antennas, but some of the info and pictures on their pages is still from the 900mhz versions

[@patrickcolclough2423]

UK buyer from Banggood, neither of my R9 antennas have a coloured band.

[@blackmennewstyle]

Asian buyer from Banggood and same experience, they said this earlier version is like the TBS T antenna tuned for both firmwares: FCC and LBT :)

[@TakeItToTheGround]

Go to the horusrc.com website They list dimensions for FCC & EU antenna's so you can check which one you got. www.horusrc.com/en/frsky-900mhz-ipex4-dipole-t-antenna-for-r9-mini-r9-mm-receiver.html

[@CurryKitten]

Thanks for the link - that's pretty helpful. Whilst the actual length of the antennas are well known to see what is 868 and 915, them giving the actual dimensions of the T-Antenna including the outer sleeves is much more useful

[@hansleatherby1032]

great video - thanks for the update wayne I havent seen any Super 8 with a yellow band - many UK suppliers are out of stock at the moment - perhaps the next batch will come with yellow bands

[@CurryKitten]

Hopefully - I think one of the problems is they all tend to use the stock images from FrSky that don't have any particular markings - so they might need to take their own pictures !

[@philthayer4087]

True about the FPV 5.8 but if you have an IRC meter you can see a 50% difference on some channels.

[@dr.razorx]

Having big trouble binding my 9R module with 9R mm receiver

[@therealmikief1]

Great series, cheers 👍. Have I missed a comparison between the super 8 and the TBS antenna?

[@CurryKitten]

No - I didn't do a direct comparison, I flew the TBS antenna against the stock, and then used the Super-8 in a later video but I kind of asked you to remember how the TBS looked. The Super-8 compares very well.

[@wingsmh27]

Antenna has blue or yellow rubber band on it what does it mean

[@DukeOfSouls]

So is that bit that goes to the controller an essential to the receiver? Trying to get a long range drone together.

[@CurryKitten]

Not quite understanding your question, so you might need to clarify a bit. I think you are asking about connecting the receiver to the flight controller via the GND/5V/SBUS pins? If so, then yes we get the power from it and we need to pass the control signal from the receiver to the flight controller to actually control the quad.

[@DukeOfSouls]

@@CurryKitten I'm talking to one of your associates about a budget long range drone and while things are getting confusing and considering I don't know sh*t about FPV outside of store bought I'm trying to peice things together. So I don't make an oops. I'm talking about the orange box on the back of the controller. I also got some questions ide prefer to ask more privately.

[@CurryKitten]

@@DukeOfSouls In that case, yes, think of the Orange box as an add-on to the radio, without it, the radio can't talk in the frequency the receiver needs. One word of caution: That old adage about not running before you can walk. Tring to do long-range (although people's definition of LR varies) before you are comfortable with building/flying your own quad may lead to problems. Although not massively more complicated these days - it's more involved than simply flying on 2.4gHz

[@DukeOfSouls]

@@CurryKitten I'm doing the best I can to learn. Just started using your simulator. Usually I would slowly climb up to it but im not fortunate enough to come across the sum of money that I'm using in this drone for a while.

[@tackleboxbrad2988]

Forgive me if anyone has already said so, but the original r9m crap antenna was actually a 2.4 antenna and now is being shipped with the bulkier 900 version of original skinny crap one. Supposedly. Also, the word is that frsky was replacing antennas for customers that had that early “wrong” one.

[@CurryKitten]

Which one, the little skinny one that comes with the R9M-Lite version? I did try swapping over between the larger thicker one in the R9M package, but they were both awful!

[@tackleboxbrad2988]

CurryKitten I should say that I don’t own any long range system but have been looking hard at the r9m. I just saw you did indeed review the thicker folding antenna. So I guess it’s whatever. Maybe the thicker antenna is tuned better for the FCC mode? I will keep checking out your r9m vids out. I’m Already an avid listener to LDO. Thanks.

[@vchan1501]

Yes, you shouldn't see much different comparing the stock antenna vs the T antenna, they are both simple dipole antenna except the T comes with a stiffer body which makes it more durable. The transmitting antenna is more important here in affecting range. By the way, R9m system still subjects to unreasonable close range (like 50m) failsafes even one can get a few KM out with 80+ RSSI. Thats strange and needs a FW fix. The latest version (181116) still haven't fix that problem.

[@CurryKitten]

Nope - I wasn't expecting any difference to be honest, but I noticed some people were talking about them as the fix to all their issues so thought it a useful demonstration. I would still call it very much a Beta product. I haven't gone down the flex route, and I've heard some bad tales about the adaptive power locking out for a second as it switches. FrSky could handle this all a whole lto better

[@MCsCreations]

Fantastic, dude. Great tests! 😊

[@CurryKitten]

Thanks MC :D

[@DavidHanniganJr]

Right on I've ripped off those UFL connectors too.

[@robrow]

Hey Curry, could you also try the directional True Mox 868 on the Tx?

[@CurryKitten]

If I can get my hands on one I will - but it depends where I want to spend my precious pennies

[@crackup007]

Very good review! The antennas have to be placed in some specific position to have better reception? Do they have any polarization?

[@CurryKitten]

You can orientate the antennas either vertically of horizontally, you just need to make sure that both the TX and RX antennas are in the same orientation. On a quad it's easier to arrange them horizontally, on fixed wing, vertically is probably easier. It's best to get them away as far as possible from any other electronics, especially transmitting ones. So quads on the end of an arm, and on fixed wing - out on the wing

[@MikeRM399]

Hi CurryKitten , are these antennas set up can be use on the flysky rc? or what would you recommend me to set up long range on the flysky si6 rc? for a whoop long range , thanks

[@CurryKitten]

No - this is very specifically for the R9 system (although you could also use it on crossfire) but the point it we're talking 866Mhz/915Mhz, not 2.4Ghz as your FlySky radio will use. Hard to say what long range is on a whoop as you'll generally be able to run out of battery before you can get that far :) I haven't flown FlySky in about 7 years so I'm a bit out of date, for a whoop something small like a Fli14 perhaps. Seems to suggest at least 500m of range which is an awful long way for something tiny

[@mbycfpv8937]

Thanks. I really appreciate all your help. I have been watching your R9 videos and finally bought the system. I have yet to maiden. Got the RSSI in osd and all bound. Downloaded most recent fcc firmware using sbus and s port. In my betaflight preview the quad doesn't react right. It spazes and sometimes does nothing. when armed (no props) it seems to respond fine. I am nervous to maiden??? any ideas?

[@CurryKitten]

On the main page where it shows the quad and reacts as you move it by hand, or on the RC tab where your stick movement make the quad move? Sometimes you can get the odd jitter or slow reaction on a computer, but if it's going crazy, it's not so great. You can try calibrating the accelerometer, and you can go to the motor tab and see if the gyro thinks it's moving. The graph up the top of this page should be absolutely flat if the quad is still

[@mbycfpv8937]

@@CurryKitten it does it only with stick inputs on the rates preview tab.. also on the receiver tab it seems way off

[@bradleyparsons]

Thank you for the clarification!

[@didactylos4diddy474]

Interesting. Orientation does seem to be key to the performance but unless you have some high tech tracking system when you change the orientation of the quad/plane/vehicle you will also change the orientation of the antenna _It will always be that way with this type of antenna_ If you insist on trying penetration tests during the winter you're probably best to find a row or copse of conifers. They tend to play havoc with RF signals especially when wet or even slightly damp.

[@CurryKitten]

I certainly notice the nulls in this type of antenna - certainly, on the XM+ you don't but then those do have antenna diversity, so you are getting a much better signal through the turns. I have to use what I have - bare trees in a line become a decent blockage eventually :)

[@tryhardfpv5351]

Any chance you can test with the antenna vertical in the L shape to see how that performs? Far less chance of getting the antenna tip facing you on a turn.

[@CurryKitten]

Probably not on a quad, still too much hassle to mount. If I was doing any serious range, I'd be find a better way to mount vertically

[@cozzy206]

Thanks any chance of some long range fpv airplane tests....thanks again

[@CurryKitten]

There's not too much of a chance based on the fact that with a slightly higher profile channel I need to be quite well behaved. But who knows, if someone sends me their long-range DVR anonymously and gives me some info about what they did, I could certainly feature it

[@DemoPwr]

Can these antennas be a substitute or replacement for the antenna on the Jumper T8SG Plus Transmitter? Thanks my friend!

[@CurryKitten]

Nope... well they might physically fit, but there performance would be awful. These are tuned to. 900mhz and you need an antenna tuned to 2.4Ghz for your radio

[@tf8826]

how big of a deal would it be to use a 868 antenna with an Fcc firmware?

[@CurryKitten]

I used a 915 tuned antenna with 868 firmware and over the range of 2km or so it was absolutely fine. I'm sure the detuning would show up more as you ventured further out though

[@outboxfpv4360]

Hi sir will R9 mini work well with Qx7 with 2x18650 batt mode? Do we need to upgrade battery

[@CurryKitten]

R9 mini is the rx, so you'd need the module for the Qx7, the R9M. It's got an external power source, if you need to power it that way, but I've used it on my Taranis's with their internal batteries and it last for a decent amount of time. It just depends how much fly you are doing

[@outboxfpv4360]

@@CurryKitten Plese corect me if iam wrong. I thought module is same for both and R9mini is old rc and the new one with inverted port is R9mm

[@CurryKitten]

Yes this is correct... in your initial question though it sounded like you'd missed the fact that a module is involved.... and it's only the module that may drain the battery in your radio faster.

[@fpvkabo]

What if you mounted the stock antenna in a L shape to help copter orientation, the 900mzh is only halt the antenna not the length of the whole T? Try it.

[@CurryKitten]

I'm told that the two elements of this linear antenna need to be kept in line to make it work. I'd actually started out in a V... which is an L in a different orientation.

[@NordicBlueRC]

So, it sounds like it's really just better for mounting and also, hopefully, for durability.

[@CurryKitten]

IMO yes, I'm not sure how well the T would survive a prop strike - but certainly better than the regular antenna, and maybe better than those antennas when they are wrapped in heat shrink around a cable tie

[@NordicBlueRC]

@@CurryKitten that's at least my hope

[@leonardvdj]

How does the T antenna for the r9 mm compare to the r9 mm stock antenna? Wondering if I should buy a T antenna and swap it out, or not bother with it.

[@CurryKitten]

There's no real difference in terms of the reception quality. The T-antenna has a slightly longer connecting lead so it's easier to mount and you are less likely to catch the props on a quad. That said, I was doing fine with the stock antenna with the two parts of the dipole heatshrinked into some cable ties

[@mikeorion5150]

What software version did you use in your R9M module and your receiver?

[@CurryKitten]

It was the latest "normal" firmware. i.e not the Flex or F.Port

[@mattiavadala7870]

Nice video, very helpful! :) I have a question: how did you get 25 mw on r9m-lite? I thought it was not possible to change it! Congratulations for the video!

[@CurryKitten]

Are you on the FCC version? The FCC version of the firmware will just do 100mw with telemetry, but in the EU we get 25mw with telemetry or 100mw without. Once flex become stable and OpenTX 2.2.3 gets released (fingers crossed) we'll all have the option of all power options with or without telemetry

[@Chilternflyer]

Wayne: What firmware(s) are you using? I don't get a telemetry option anywhere on any screen on my 9XD (opentx 2.2.1) ( I'm using a red R9M with a slim+)

[@CurryKitten]

I'm using the standard firmware on the module and R9MM, with OpenTX 2.2.2. For the LBT firmware it only allows telemetry on 25mw, so don't know if you are binding at a higher power output which would stop it ?

[@EnglishTurbines]

How are you getting the RSSI in your OSD Wayne..?...What is Telemetry RSSI?...I just get mine from Channel 16...in iNAV.

[@CurryKitten]

I found the RSSI signal from ch16 to be a bit erratic to say the least, so I'm pushing the telemetry RSSI signal you get sent to the radio back to the flight controller in another channel like this : www.currykitten.co.uk/getting-the-rssi-value-to-show-in-your-betaflights-osd-frsky-based/

[@outcastfpv7655]

Remember enjoy life there's plenty of time to be dead later... Hahaha. Good advice. Thank you for this series on this particular subject been really helpful.

[@flyingfrogfpv411]

Interesting stuff buddy thanks again !!!!

[@garyjohn1076]

Loved watching ya stuff CK. I stupidly followed Dronemesh and bought the R9M to mod to a Flysky fsia6..... Obviously it doesn't work and can't figure out how to wire the reviver... Got it to bind but no be recognised by the FC.. can't afford frsky Tx (Married, with a 2 boys under 2 and Twins on the way for Christmas! ) Any ideas how to get it to work?

[@CurryKitten]

Well, I haven't got an i6, so I'm a little unfamiliar with it, but I've taken a look at what's involved in the mod, so I guess it's a case of pinning down where you got to and what works/doesn't work. So did you get the 5cv/GND/PPM solder points on the i6 and bring them out so you can plug them in the module ? It sounds like you at least got the module some power if you've been able to bind it to the rx. As far as wiring to the FC goes on the R9mm, you'll want to hook it up as if it was an SBUS rx, and use the SBUS out, GND and V.In pads. Make sure that UART has serial selected and that your serial provider is SBUS. How much of that have you done and is working, and how much doesn't ?

[@garyjohn1076]

No1 thanks for replying! Most wont or carnt so REALY gratefull for you help! Im new of sorts to the FPV stuff. Iv been able to build a few quads. nothing amazing just basic stuff. But iv become well addicted! Anywayz. my knowledge only extends to Sp racing F3 when it comes to seting up stuff.. basic ibus ppm... so iv tryed getting my head round the next step up with Sbus in.... out... Arrr! iv got the ppm conected to the F6 to R9M ppm but Im still learning... so my question is is tbe F3 able to have SBus? Iv always refered to Painless for his videos on F3. but i dont beleive he had covered SBUS on SPs Again thanks for help! And im not just saying it fella but keep up the good vids man! i enjoy watching ya channel as iv been a sub for a long time now! you are easy to listen to and the content is always clear and informative but fun to watch to! keep up the quality stuff bruv!

[@CurryKitten]

Happily enough I've got an SPRacingF3 board in front of me (allbeit a copy - my original exploded one day) I've connected my SBUS rx to the side connector (labelled io2) if you look at this video kzbin.info/www/bejne/pXzQhaufq62Nd9k at around 6m49s that's the FC with the rx connector via SBUS. The pins are (from left to right) ground/5v/signal and then you just set it in betaflight as SerialRX on UART3 in the ports tab and then in the configuration tab serial provider is SBUS. If you've connected an IBUS rx before, I think it's really very similar and odds on you may be able to use the same UART (I can't remember if one is inverted and one isn't so don't hold me to that). If you are stuck and want to get me some more detail, send me a pic or 2 ([e-mail])

[@garyjohn1076]

You are a legend sir! When i get a chance i will give it a go. im alit more positive about this now with your help! will let you know how it goes. If you are ever in wales give us a bell!

[@TheMadmacs]

@@garyjohn1076 yeah i think you tell the i6 to send out ppm and the r9 module does the sbus bit, FC side should be normal sbus set up..

[@meatheadfpv5348]

Thank you for the info help me out lots this yellow band was doing my head it wasn’t sure if it had to be facing one way or another 🤣🤣🤣

[@nerdCopter]

+1👍 Thanks a bunch C.K.

[@CurryKitten]

No worries, glad it was useful

[@nerdCopter]

Received my Super 8 and Slim+ Antennas same day from two different vendors; I had to re-visit your vid to verify rubber band colors. Super 8 has red band, antennas have blue band. FrSky :/ pick a color, lol. Thanks again!! 👇 Preliminary test show i need my super 8 horizontal on my xLite, can you verify?

[@MrJarrod]

You really got to try the TBS tuned antenna. Pro long distance pilots swear by them.

[@CurryKitten]

If I was doing any real serious distance then I might be trying it out - but as far as quads and their range go, the basic Super-8 I have is doing fine

[@DavidOwensuk]

Okay are we not allowed to use 100mw? 25 mw will provide only 50% of the range

[@CurryKitten]

If you are in the EU... the legal answer is no, but the more practical one is "will anyone know" ;)

[@alchemicalanarchist]

The specific tuning is meant to mitigate cell phone interference which can cause a failsafe is you are not using the correct tuned antenna for your region.

[@CurryKitten]

It's an interesting idea - but what's your source of information on this one ? I'm in a country where I use 868Mhz with a antenna with a range of 860-920, with phone networks putting out transmissions the 900 band, but I'm not seeing any issues. Fly close enough to any antenna that's transmitting on a very high power though and you'll generally see issues no matter what frequency you are on.

[@alchemicalanarchist]

@@CurryKitten My source is Trappy and Bruce from RC model reviews. Trappy explained some of this in a talk he did with Snake where he explained why the tuned antenna are needed and are a thing. And I was watching Bruce put the R9M module on a bandwidth scanner and the FCC bandwidth I use is about 900 to about 930. That is just a 30mhz band that is being used by the R9M module and the Tuning of the Antenna is needed to match this. I dont think LBT really goes from 860 all the way to 920 that is a range of 80mhz. I think their quoted range for LBT of 860-920 is just marketing. You are correct to use LBT frequency in a place with 900mhz cell phones. That is how you are supposed to do it. In the USA we use 868mhz cell phones and we have the 915mhz FCC band for our radio. This is is the entire reason for the tuned antenna. To separate LBT and FCC to their respective frequencies.

[@CurryKitten]

Forgive me if I'm misunderstanding, but you seem to be confused between what a module trasmits on and what the frequency range of the antenna is. Over here in the UK, we are using 868Mhz, and I would expect (although I haven't got the appropriate scope to check) that the range is probably about 30mhz as well. The fact that the antenna is usable from 860-930Mhz doesn't mean that we're transmitting over that wide frequency band it just means that we get max gain at 900Mhz (where it's tuned) and that gain falls off, to the extent of a loss as we get further away from it. Sure, as I mentioned, you get a gain from using a tuned antenna, but using this 900Mhz one doesn't mean you are pushing into the GSM band, nor does it mean (as demonstrated) that you are going to fall out of the air and failsafe.

[@alchemicalanarchist]

@@CurryKitten The first batch of antenna were tuned for 900mhz to split the difference between LBT and FCC But they are not ideal for either frequency. This is the same thing that TBS did with their Diamond antenna and T shaped Immortal T they are both tuned for 900mhz so they can sell them to all markets. But Frsky has gone with specific tuning for the Regions. TBS also has some tuned wire antenna and TX antenna with plans to bring out even more tuned antenna in the future.

[@alchemicalanarchist]

Its better to think of the tuning as being done for Accuracy, not for power. Because the band we are using is a Cell Phone frequency we can get random interference that will cause RXloss. So they came out with tuned antenna to lessen the effect and chance of this happening. If you fly in a region with the wrong frequency on the radio and with the wrong antenna you open yourself up to the cell phone interference because you are not tuning to a frequency to avoid it. Lots of people on crossfire had failsafes because they were using the wrong frequency. And when you fly on the wrong frequency you can get cell phone interference because were are using cell phone frequencies.

[@frasersteen]

Very useful info

[@charlesphillips1642]

Mine did made a big difference

[@frankbarajas]

I know I going to shoot myself for asking but I'm curious about all of this and even what the letters "LBT" actually mean? I know it's for use Europe but don't what the letters come from, as FCC comes from Federal Communications Commission. A quick look on Google gave me Local Body Tax, Large Binocular Telescope, Lesbian Bisexual Transgender, Little Big Town, and my favorite: Legs, Bums and Tums...lol Good video and very informative. However, at the distance you were flying in the video is there a need for R9? I really don't understand the need for R8 since aren't we not suppose to fly beyond visual line of sight anyway?

[@drdrechronik]

LBT=listen before talk - radio transmitters first sense its radio environment before it starts a transmission

[@frankbarajas]

@@drdrechronik - Thank you. I hadn't seen that version yet. I did find "Low Band Transmitter" which looked promising. I still prefer my favorite translation of *LBT* as *Legs, Bums and Tums* and I doubt I'll ever get that one out of my brain...lol

[@CurryKitten]

LBT means "Listen before talk" it was brought in because of some EU legislation. Essentially, as the name suggests, it listens on the frequency band before deciding which one to transmit on. There's no real need for the R9 in terms of the distance I was goin - I do have these weird RF spots in my field that take me out of the sky on 2.4 though (I describe these as the dodgy bits) nobody is supposed to be going out of LOS, but of course people do, so this is a cheap solution. That said, these RX's can actually be cheaper than something like an XM+ right now, so you can see the appeal. Not quite as plug and play as 2.4 though - still very much an "in development" system.

[@CurryKitten]

You beat me to it - there I was typing away and I needn't have bothered :D

[@frankbarajas]

@@CurryKitten - Thanks! Ok, so if we aren't experiencing any issues with 2.4 GHz then there's no need to go to the R9 setup? It just seemed like everyone was jumping in and I didn't want to get left out in the cold again like what happened with the old 72 MHz and 75 MHz Radios that were practically abandoned by the RC world.

[@richylad71]

Ricky Gervais on drones 👍🏻😀

[@philthayer4087]

They sent me blue bands on my Rx and red on my Tx.....

[@DavidOwensuk]

Good useful video

[@EnglishTurbines]

Using a 915mhz antenna on a 868 reciever is very bad...the VSWR is terrible...Coloured bands..??...Not a band with either 915 or 868 written on it then...? Nice video Wayne..rssi looked more stable to me.

[@CurryKitten]

Writing down a number would make too much sense and people would know what's going on - where's the fun in that? :-P

[@EnglishTurbines]

@@CurryKitten Oh yes...how inconsiderate of me...Just off to think about what I have done..🙄🙄🙄🙄

[@SkipperDrones]

Nice video

[@wingsmh27]

Got answer in just 1 min

[@CurryKitten]

Awesome - saved me some typing :D

[@markwood9751]

I know a lot of people use the 800-900MHz for "peace of mind" especially when flying areas that require penetration such as heavy woodland, warehouses, buildings etc. Take the racers you saw at the drone show for example... Everyone was running crossfire. That I see as being totally pointless as the track was less than 80ft long with no heavy los obstructions and let's face it, not like you could loose the quad inside a netted enclosure anyway! But is there a reason you aren't swapping to 2.4GHz on your video? This too has comparable penetration when flying obstructed and compliment it! ( I just know someone will come back with "because its lower latency on crossfire")

[@CurryKitten]

Because it DOES feel different on crossfire. I thought the idea was snake oil as well, and I am at best an average pilot so if I could feel the difference (and I had both 2.4 and crossfire on the quad to do a very quick swap over - have a look at the video) then a decent pilot will really be able to feel the benefit. 2.4 video doesn't make much sense on a 5" quad, the skews are like tree hooks. 2.4 might make a more mainstream return though - furious have a goggle module, Menace have a patch, but ImmersionRC can't be convinced there's a market to make a 2.4 RapidFire though

[@oranzoar]

To me your reviwes lacks the ref point of when a fail safe actuall accure. Its no about rssi amplitude and variance, its about failing point....

[@CurryKitten]

Well, there are several reasons for that. If I were to go and show me flying away until it went into failsafe, then it only gives one point of data, and that is: In these particular environmental conditions at this particular geographic location, at this height and distance, having configured the R9 this way in this quad which has this particular layout - a failsafe occurs. It doesn't really help you predict what yours will do as all the variables will be completely different. Instead what I'm doing is flying in what I term to be typical mini quad conditions and looking at what makes the signal weaken and what effect the different antennas have

[@oranzoar]

@@CurryKitten and yet , it wold be halpfull to know what rssi values are in the failsafe niegberhood , and in what condition youll get close to that. For that matter it not even clear (at least not to me) how rssi interact with distance and condition, or even if its linearly correlates to it...

[@CurryKitten]

"It depends" is the all-encompassing, and slight annoying answer. I started off by using the RSSI signal on ch16, I was able to get my RSSI value sown to single figures on multiple occasions, but without a failsafe. If I take the RSSI signal from the telemetry signal then it stays higher, and also doesn't failsafe. So hard to tell really, as I'm not going to simply go as far away as I can - at least not on a quad - and then wait until it drops out of the sky. As far as I'm concerned in "normal" quad flying the R9 does well as far as the signal strength is concerned... and that's the basis of what I'm reviewing at the moment. I wouldn't be able to talk about range and where the failsafe reliably happens until I get this into a plane with a decent RTH system. RSSI will give off a reasonably linear fall if you fly away and hold that exact atitude, although you can have big fall offs sometimes. What we're seeing on the R9 is that getting the rx antennas just a little into the null point will result in quite a large drop off in signal. So extrapolating this out - you might find that as your signal gets weak a long way out, simply turning will drop off altogether. Hard to tell until that gets tested in real-world conditions