Hold my beer, I'm going long range

[Burkeomatic]

I want a long range set up, not necessarily for long, brutal range, but something longer than 500m. I was looking at the TBS set up, but then someone on RCG turned me on the Express LRS. Basically, it is an open source set up similar to open TX that operates in the same capacity as others. What is really cool, is they make PWM receivers for it, so you don't even have to worry about soldering up CRSF connectors, and you can quite literally use any flight controller you want, from the $25 sparrow to the most expensive ones available. 

Now, there are multiple vendors, and options to build your own, but I don't feel like building my own. Also, you can have the choice to go 2.4ghz or 915 mhz. The 915 is longer range, and has better penetration, but there are latency issues. The 2.4 has better latency, at the expense of range. Given the fact where I live, and the fact I don't feel like taking a long car ride to go fly, I have a couple of places that I fly near my house. Both of which provide some airborne access to unpopulated areas. 

This is my most frequented flying area. You can see the football field/track field, surrounding trees and school I typically fly LOS over. The orange circle represents the current range on my Flysky radio with upgraded antennas (not really sure it did a whole lot, but hey), but you see all of that unpopulated area to explore to the east, and the green line is about as far as I would want to go, which is about 1500m. Plenty of unpopulated stuff to fly around and explore, right? So my main goal was untethered access to this area, which people claim a modded flysky radio can do, but I call BS on that. 


map by Burkeomatic, on Flickr

Ok, so at this point I have realized that basically every long range system is going to be complete overkill, but if I get greedy, and decide that I want to go further, I can take off at the highschool nearest me. It isn't nearly as friendly to fly LOS at, but a better FPV spot. Keep in mind, even the crappiest antenna designed for short range on this does 3.4km at 100mw. But this is what that range would look like. Yet again the orange circle is my current range, and the green is 3.6km. 

map2 by Burkeomatic, on Flickr

So this dude did some range testing, and he was getting incredible ranges at 100mw, I bought the el cheapo version which "only" goes up to 500mw, the pro which costs a whopping 9 dollars more goes up to 1000mw. 



This will plug into the back of my jumper T12. 

www.racedayquads.com/products/happymodel-2-4ghz-es24tx-express-lrs-tx-module?currency=USD&variant=39420930064497&gclid=CjwKCAjw7vuUBhBUEiwAEdu2pLhMo6IC3zIJV1pBadZUW-MuaQUFwC2Hd8UtTCb7FQ60UFLJzj3fuRoC7rIQAvD_BwE


I bought one of these receivers to try. 

www.racedayquads.com/products/betafpv-2-4ghz-micro-elrs-pwm-receiver?currency=USD&variant=39719887175793&gclid=CjwKCAjw7vuUBhBUEiwAEdu2pIk-TA8Eh9D2Nz0_5ku-Fw5JmHx9v5wmIIAle-XpwggOabW-Z2jQGBoCI5wQAvD_BwE

Also one of these

www.racedayquads.com/products/happymodel-epw5-2-4ghz-elrs-pwm-receiver

If you are keeping score, that is enough stuff to fly two planes at least 20km away (I tend to be conservative with my estimates) for under $60. If i would have known about this sooner, i would already have it. These receivers are about the same price as your flysky 6ch receivers too! Holy cow, I feel like I have been missing out on a lot. Guess that is what happens when you read one single forum. Anyways, if I want to move to the ultra long range, I can buy the same set up in 915mhz for about the same price. It blows my mind that given enough battery, I could fly a RC plane to the Mexican border if I wanted to for under $100. 

I partially justified this to myself, because I had 3 receivers loaded up in my cart on amazon for about $40 bucks. I decided that 9 receivers was enough, and I could deal with switching them around, But then, I found this, and I am glad I didn't waste money on receivers that only go a quarter of a mile, and got some that can go for miles for the same price! So mentally, I told myself this only cost me a $30 buy in, and I was going to spend the rest anyways. I kind of feel like every receiver I have bought up until this point was a waste of money, lol. 

[Burkeomatic]

Holy cow, it came in already. This is why i buy from RDQ.

[Burkeomatic]

Ok, I have it set up. It was a steeper learning curve than it had to be.

I had to learn a fair bit about my jumper T12 (in the process, I figured out why it wouldn't bind to the FS receivers, I needed a memory card in it with the right files). I ended up having to update the firmware on that.

So step one, done, update firmware and load proper .lua files onto my jumper T12.

I went to update my happymodel TX via wifi and I couldn't, even following the directions to the "T"
Turns out, the .lua file you load into the radio needs to match the firmware version of you ELRS tx. So I had to pull it back apart and do it via USB. No biggie, it worked out. Once I plugged it in, I could connect my TX to wifi... sweet.

Step two, Update ELRS TX add on. Done.

Then I updated the receiver, I did this wirelessly. The wifi signal on the receiver sucks though, so I had to put it next to my computer.

Step 3, update RX, Done.

When you flash firmware on these, you put in a binding phrase, so whenever the firmware is flashed, the binding phrase is remembered. Then when you turn it to the corresponding model in open TX and you power on your receiver, instabind! The binding process is so easy it is stupid.

Fired it up, and it worked! Now I just need to learn how to program my jumper T12 like setting up failsaifes and stuff and I am in binness.

These are the instructions I used.

oscarliang.com/setup-expresslrs-2-4ghz/

I would damn near recommend this to a beginner. If you are tech savvy, and going to have to figure out how a radio works anyways, may as well pay a few bucks more and get a "lifetime" radio like an open TX one. A bit more learning on the front end sets you up pretty well.

Obviously, if you want a set it and forget it parkflyer, the flysky is good and ain't a thing wrong with it. I don't hate for one second that I bought it nor do I think it was a waste of money.

[Burkeomatic]

So I hit one snag. I got everything hooked up right, but then, my 3 position switch to activate the flight controller modes was only 2 position, meaning my plane would only switch between stabilized and gyro mode and no manual mode. So after screwing with my radio for hours trying to figure out what I did wrong in it, it turns out I did nothing wrong at all.

The problem was with open TX, specifically the receiver I bought. I bought a couple of PWM receivers for simplicity. However, there is a rule in open TX, and that rule is that CH5 (AUX1) is binary, meaning it only works on max and min, effectively making it a two position switch, no matter what my hardware was set up for.


By default, the PWM receiver is mapped to CH5 being Output 5. Output 5 is AUX 1 which only allows 2 positions 1000 and 2000, and I wasn't able to get that 1500 position I wanted for manual flight mode.

I got on the ELRS discord and asked, and they stated that I should change the receiver output 5 to CH6(AUX2). So I connected my wifi, made the change in my rx, and then mapped the button I wanted on my TX to CH6 and it worked like a charm. I got the failsafe set up on it and it works perfectly.

This is what it looked like when I was done..

Screenshot 2022-06-11 083119 by Burkeomatic, on Flickr
Pretty neat, I can even invert the signal in the receiver as not to have to do it in the TX as well, or assign the outputs on my receiver for whatever I dang well please. If I didn't want your standard AETR, I could rearrange it however I wanted no problem. 

[Burkeomatic]

ELRS maiden completed. I used the drift as I have never really had any issues from it. It is the real deal. Everything went perfectly (Except for a kopilot issue, which is a story for another day, and was easily fixed, and completely unrelated to anything in this thread) I was able to fly all around until my camera started losing signal. I can double the output of the little AIO cameral in it, so i may do that. There are warnings not to let it sit at higher power levels without wind blowing over the unit (it doesn't really get any airflow, not sure how much difference it would make).

But then I question, why do current 2.4 ghz TX have such garbage range. I know some of the pricier ones do better, and the flysky is no ringer by any stretch. All i had to do was plug a $30 module into the back of my radio and I now have 30km of range. Pretty mind blowing.

[Burkeomatic]

I have found a drawback to ELRS.

They don't support SBUS and their pwm rx only goes to 5ch.

They don't plan to support SBUS as they are kind of elitist about CRSF and think essentially anything but CRSF is shit. They were also dipshits when I asked about it.

So I have my nice twin king, which I need 7 channels for. I have a gyro which supported this. I don't want to run a ''real CRSF'' flight controller because it has tons of functionality I don't need, and I don't want to alter the wiring of my plane.

Essentially, ELRS is right on par, maybe a little ahead of the curve as far as things like quads and 5 channel fixed wings or something using a F4 flight controller, but is miles behind and completely out of touch with ''real'' fixed wing LOS planes that are anything beyond a simple foamie.