New to forum, new to "real" drones, looking to increase range.

So there are two distinct places you can have two antenna, on the transmitting side and on the receiving side.

On the TX/Transmitting side if you split an already amplified signal in half like you said basically half the power is going to one antenna and half the power is going to the other antenna. I haven't really worked with any setups that have multiple transmitting antenna I think in most cases you are best off getting a higher powered transmission from single antenna rather than adding another transmitting antenna at the same location. There may be cases like a ground station where it makes sense to have multiple directional outgoing/transmitting antenna (thinking of cell towers with all those directional rectangular looking transceiver antenna, a transceiver just does both transmit and receive, usually not at exactly the same time but can flip flop and utilize the same antenna for both).

Regarding the second half and having two antenna on the receiving side, this is what a "diversity" module is for, check out "rapid fire" from immersionRC or "LaForge V4" (or whatever latest version is). Basically these receivers take two antenna inputs and they "check" to "see" which one has the strongest signal, whichever one has the strongest signal gets passed along to the receiver signal amplification/filtering circuit and from there the video signal is passed along to the display/output. I think rapid fire actually somehow combines the signals whereas laforge just quick switches between them (you can see the change in vid quality and hear it click when it changes, can also display on screen what signal strength each antenna is getting and some other things)
 
Damn, too bad they don't make these in china or some other place, shipping is 30$.

I guess I'll have a directional reciever for the FPV footage? Does that work well?
By the way, I just watched a couple of tests, and it seems that pagoda antennas work better than cloverleaf ones, so I guess I'll order one of those.

It seems to me here the drone certification is basically read a couple of pages and do a test, so I think I'll do that, because then I can get 2w transmitters for the FPV. But, how would i go about putting the signal amplifier on the drone itself? I mean where to connect the leads.
 
Yah not sure honestly regarding just using a directional antenna since I've always only used the clover leaf style circular polarized ones alone or pagoda ones in combo with a patch antenna so it usually only switches over to the patch when I get pretty far away or high up.

It will work with just directional but if the cone or "signal pattern" for it is too narrow then it might be hard to stay in the cone (especially for me with goggles on my head tends to bob around like Ray Charles but with fixed ground station directional alone could work well I think)

Yah in the US for now at least still just register with FAA if flying with all FCC certified gear. If not then need HAM general technician license which is similar read up for a few days learn the rules and a bit about various bands and other rules and then pay a few hundred to have the tests administration and get your pass/fail.
 
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I guess I'll just stay with the pagoda then, because I don't know the cone and I don't have a tracker.

Should it stick up or down the drone?

Does this one seem good?
www.ebay.com

Realacc Pagoda RHCP Antenna 65mm 5.8G 5dBi Panel Plate Omni Directional FPV | eBay

Gain : 5dbi. Directional : omni-directional. 1 x Antenna. Color : Black/Red/White. Connector : SMA/RP-SMA. Power : 50W. Weigth : 9.3g.
www.ebay.com
It's from china, I don't know its real Realacc.

Or this one:
www.ebay.com

Pagoda RHCP FPV Antenna 5.8GhZ 5dBi Omnidirectional SMA RP-SMA | eBay

Gain : 5dBi. Connector : RP-SMA or SMA. This is considered normal - therefore, a change in battery capacity is not covered under warranty. Battery life is not warranted and will vary depending on usage.
www.ebay.com
 
They look fine to me but hard to say quality wise, the brand sounds familiar but for the most part I've used either the ImmersionRC ones that I bought along with the HDO goggles or some generic no-name ones. Have also used Luminier AXII I think but definitely always hear good things about them as well. Making sure your antenna are all as well connected as they can be and as well made as possible helps a lot so it's probably worth spending a little more here (also difference between high and low end isn't that big since it's just a conductor that is shaped the "right" way and with the "correct" length and impedance, so it's really just about precision quality control/part sizes and assembly rather than anything fancy with the materials themselves).

Things to keep in mind are where you will mount it on the quad so it doesn't get into the way of props and ideally up away from the electronics and frame a bit but without dangling around where it is going to get knocked down into the props (another one of those balancing acts, you want it away from the carbon frame and electronics a bit but not so far out that it's dangling all over).... I generally like the style of ones you linked though think they are good in between size on the antenna connector, have also used ones that are just the little nub on top basically and go right into a "pigtail" extension/connector for the antenna.
 
I gave myself a second thought.

Would it be CHEAPER, to build my own drone? I have a 274$ budget for this. Could I achieve higher flight times than 25 mins?

And have 1920*1080 HD video recording with a stabilized 3 way gimbal? Or just buy the JJRC x12 and upgrade it as I go?
 
Nah under that budget it's hard to build anything better really. I think when you start looking at the prices for like a DJI inspire or Phantom fresh out the box then looking at a DIY rig makes more sense for the cinematic things (or building a cinewhoop for flying indoors or tight spaces but wouldn't expect anything near that kind of flight time). If you have big blades relatively speaking you can get better flight time in general, also just maintaining hover takes less energy if it's not windy than say racing around or doing acrobatic flying with a frame designed for 5" props or smaller.

Start up costs for going DIY are basically the transmitter and receiver/display/goggles (however you are getting your video and displaying it on the ground). The plus side is most of these things don't get broken (at least not as quickly as quads can) and can be used between many quads if you get something like the Jumper T16 with 4 radio transmitters in one (it only uses one at a time but can talk a handful of protocols allowing it to work with spektrum receivers or frsky receviers and handful of others).

If you win the lottery or price becomes no issue at some point then DJI digital everything and just using that transmitter could work too but definitely different price tiers for different things.
 
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There is Stu from UAV futures who does a 5" or so build every year basically under $100 but it is generally components you'd want to replace pretty soon (guess worth a look though to see some cheaper parts lists and what might work as starting point without breaking the bank)


Again though this is more geared towards racers or acro pilots rather than cruising high and getting nice shots of scenic places, for that type of build probably get camera like you said with gimbal etc. and go larger frame larger props etc. but that means bigger motors where price starts going up. If can find a good deal on good sized motors then can maybe do it cheaper DIY but like I said all those up front costs of separate transmitter that works across models etc.
 
Yeah, I don't really plan on racing, lol, maybe in the future, but defenetly not yet.
You said the bigger props, and I was thinking about it.. Would it be a good idea to put slightly bigger, maybe carbon fiber props on the quad? Would it ruin the hover? Would it give it a bit more flight time? Won't it stress the motors too much?
 
Yes yes and yes basically :)

Basically the biggest props that will fit on a frame will result in the best use of that frame size. A bigger prop pushes more air per revolution, that extra push doesn't come for free it takes more amps to get the torque needed to accelerate a prop from one velocity to another and the more mass in the prop the more force you need to accelerate it so at some point you'll overload motors that don't have thick enough windings or strong enough magnets to achieve the desired acceleration, basically the escs will leave the mosfet gate open for too long trying to get the prop to move and will cook the motor (or esc whichever handles less current becomes a fuse). If the motor can handle the current it will just get a bit warm. How fast a quad tries to correct for moment to moment changes happening is basically the D term in the PID loop if that value is too high the FC will tell the esc to "try" much harder to avoid overshooting the target angle/acceleration. So basically if you are using bigger props but lower D term and willing to accept some wobble on fast moves then the motors should stay relatively cool (assuming roughly sized correctly for the motors or vice versa). Ecalc.ch is the way to check how many amps you'd need roughly given a prop size and other parameters and best way I know of to get any idea about flight time or other characteristics before buying/building. Unfortunately license to unlock all the custom inputs is like $50 a year but think still worth it in time and parts savings if you plan to custom build eventually too.
 
Thanks. And, does it make sense to get carbon fibre props of the same size/same thrust? I heard it's good, but i've also heard it's bad. What do you think? Are there lighter ones that have the same thrust? If yes, that would work IMO.

Also, stripping the frame for less weight? I mean, taking off the rubberized top, the plastic casing.. All that stuff

By the way, I have an electric motorcycle that i built, also a gas one, so I am fairly familiar with the "physics" of how engines and stuff work, inertia and torque and stuff. Just not aerodynamics! I know some stuff, like how it works, but not everything, i'm still learning.
 
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Oh yah same boat there :D aerodynamics is complicated business and figuring out "optimal" power to weight ratio to get the best flight time is definitely a matter of guess and check with ecalc.ch for me too. I have experience with building my own electric skateboard that required me to get a pretty good understanding of BLDC motors, torque, etc. and what the limits are on things but same in terms of being lost once airfoils etc. start to come into play.


^^ haven't watched this yet but probably some relevant info



^^ watched this one but just flight really not info more see if you can tell a difference from the footage compared with other Mr. Steele videos rather than his opinion/knowledge on the topic.

Regarding stripping weight, the smaller the quad is the more of an issue this is going to be basically. Smaller quad == smaller props == need more speed on those props to get lift at all. So in the case of the "tiny whoop" or "micro class" quads stripping any weight you can is a big benefit (the percent weight of a extra thick big wire becomes substantial compared to the whole weight of the thing at this size, the bigger you go the less these little bits of weight are compared to the whole weight of the thing).

My hexacopter build that is closest to a "cinematic" style setup and made for longer flight times does have CF props but I figured at 13" if I found plastic ones they would be weak or heavy and I think other option is wood at this size but figured the CF might be a bit more resilient if/when I crash them into the ground (so far has been just a bit of hovering and cut the props into the grass one time, no damage to them but have a couple sets of backups I ordered all at the same time since was slow boat shipping to get them so had to wait a month)


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Ordinarily my hexacopter build would have cost a ton of money but got lucky on the motors and got a mostly working set of 6 for like $20 from a very generous forum member here who just wanted to get rid of un-used equipment.

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Can see my Tarot 680 Pro frame based build (hexacopter) here too http://quadcopterforum.com/threads/tarot-680-pro-build.21344/

I just added a new GPS/Compass to it and got it configured/working in Betaflight but still need to test the set Home position and Return to Home features then going to try flashing iNav and see how the "Waypoint Control" works there since I hear it's more advanced.
 
Oh, nice!
Yeah, the drone is 437 grams, and looks like this:
1589566190675.png

But, I have a question. So i said I want range, right? Well, what do you think I should do, get a pagoda tx and rx, or, leave the stock dipole, and maybe build/buy a 5-8 turn helical? It will be mounted to a tripod that I can aim any way. (Used to be a telescope stand)
 
Vikingimike01 said:
Okay, thanks. I think I'll end up getting the JJRC X12 after all. I'll look into more directional stuff, as I'll be facing the drone most of the time.
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An interesting discussion, thanks both.

For what it is worth, I have a JJRC X11. I've been increasingly impressed with it as it is robust and well thought out. I have crashed it badly, twice, against a wall and a roof, both times totally my fault, and it has survived, a little battered, but still functions. Even though I was initially disappointed with the 2K camera, in good light, it returns reasonable, but unstabilised, results. I've recently upgraded to a 4K camera, which has a little stabilisation, built in, which makes all the difference. My point is that the X12 appears to have many worthwhile improvements over the X11, so sounds like a good drone.

With your budget, would you not be better off with a Mavic Mini, if you could stretch the budget a bit? Maybe it will be easier to fiddle with the X12 than the Mavic and that will drive your decision. It all depends upon priorities, I suppose.
 
Yeah, thats a bit.. double actually from Europe.. And, I have ordered the X12 a few hours back.

But, thanks for your feedback. Do you know how long you had it for? Sounds like a good product. I used to have an other drone, I have my HS120D, i flied 10+ times and never crashed so far.
 
I've had the X11 since November and use it mainly for videos. I used to sling an action cam underneath but with the 4K camera upgrade, that is no longer necessary. I broke an arm in one crash (totally my fault) so had to take it apart to replace the arm and the camera. I was impressed with the design and quality of the build but then I had only used 'toy' drones before the X11. I think you will enjoy the X12. It sounds considerably better than the HS120D.
 
Well, the HS120D, says it has 300m range, but the FPV starts lagging at 100m. Like, really badly. Two, or three second lags. And, it can't do with any wind at all. 10km/h wind in 1/3 speed it would just go with the wind, 2/3 speed it would hardly go forward.

What 4k camera upgrade did you get for it btw? How has it affected flight time?
Also, what FPV range do you get? It's advertised as the same range as the X12. Does your phone also connect to the remote like the x12, or that one connects directly to the drone?
 
Vikingimike01 said:
What 4k camera upgrade did you get for it btw? How has it affected flight time?
Also, what FPV range do you get? It's advertised as the same range as the X12. Does your phone also connect to the remote like the x12, or that one connects directly to the drone?
Click to expand...
The camera upgrade was a direct X11/Bugs 4W replacement from rc spares but does include a little software stabilisation, which is helpful.
As I was flying with an under slung camera, which was now not necessary, flight time has increased to a little over 15 minutes but my film shots don't normally take that long. The batteries have been used quite a bit so performance is slightly down over when they were new.
I loose WiFi contact with my 'phone at around 200m, at a guess, but then it connects at 5Ghz, so range is less than that of the controller. It connects directly to the drone.
I've never lost contact with the drone, but I don't fly it out of sight even if it is a tiny spec. The controller contact always has several bars and seems robust.
 
Oh, that's weird. How high have you been flying? It should have more range, 300-500 according to the website.

I guess, the X12 is better this way, it has a built in reciever in the controller, so the range is more, and I'm planning to upgrade that antenna for even more range.

But I don't know if I should just get a helical reciever for the controller, or switch both reciever on the controller and transmitter on the drone to a pagoda.
 
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Okay, I guess i'd need a circular polarized antenna either way on the quad. So one pagoda there, one helical reciever, and boom long range. I'll test how well it works compared to stock in a few weeks when I get my drone.
 
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