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Questions about Servo Cables

tj272004

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So I am trying to connect my FS-I6B to my APM via the use of servo cables. I ordered some and then realized I had ordered the wrong type, I order M to F instead of F to F. However, I do have M to F jumper cables and was wondering if I would be able to put the F end of the servo cable into my radio and then put the jumper cables F end into the M end of the opposite side of the servo cable and then connect the other F side of the jumper cable into my APM. So essentially, this wiring would go:

Radio --> Female Servo Cable --> Male Servo Cable --> Female jumper cable --> Female jumper cable --> FC

It sounds like it would work but I am just unaware if the jumper cable would be able to transmit the signal coming from the signal wire on the servo connectors.

Thanks in advance.
 
That sounds like a mess, but maybe a picture would help. Just the way you're describing it, it sounds like it could work for bench testing, but I wouldn't fly it like that.
 
How do you usually attach your FC, I don't have a PDB and my FC doesn't work as one, for the radio at least, so at this point I don't really know what else to do, lol.
 
Is this an APM 2.8? Not familiar with it, but I found this
QuadHookUp800B.jpg
 
It looks like your receiver and FC both have huge sets of pins, so you just need the right servo connectors.

I feel bad, because it's the second time I'm saying this today, and I realize we can't just "buy our way out" but...

Why are you using this particular hardware, and what are you making?
 
Uh, so what your saying may be pretty much the most sensible way to get around this problem, as in to just buy F to F servo cables. The only thing though is that I wired it the way I believed it to be right, based on a similar diagram, and the radio didn't seem to get power, so maybe its a user error, or maybe my version of the APM is not able to supply power to a radio.

So, I'm using this equipment instead of basically any other more sensible, more reliable, and most likely cheaper equipment because of the one thing I need out of it. I have a little experience with racing drones, so I decided to make a project for a tech competition. I am attempting to make a drone that has attachments that can benefit say firefighters, police, or any other thing. But, the thing is is that it has to be autonomous, and the APM allows me to program commands in the mission planner via the use of Python. I did not envision this peace of equipment being very difficult in my case (though I am sure it is not its fault, but rather mine) and I would have possibly have tried an alternative project had the deadline not been relatively close, and with the hassle of ordering new parts and shipping, I decided to stick with it and hope I learn for the next time.

Any way, thanks for your help.
 
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Sounds like a great project, though a high bar for a first build.
You're not dead in the water, we just need to be pragmatic. I find that sometimes, just trying to explain a problem well enough that someone on their computer can understand it, I end up understanding the problem better myself. One thing you can do is get a multimeter from the hardware store. With that we can find out if your FC is putting out the 5volts we need for your receiver.

I suggest you take some pictures with your phone of what we're working with, and we can figure it out.

I'm foreseeing some problems that I may be wrong about when I get the full picture. For example: you're running 3s on 1120kv motors. Those numbers don't add up to me... How big a propeller are you trying to swing?
 
So I'm not actually running 3S, it's just that that's the only battery I have that's working right now. I plan on using a 4S battery, with a 4-in-one ESC with 40 amps per channel. Currently, I plan on using a tri-blade propeller that is 7x3.5x3, but I'm not entirely sure if that is going to work. The recomended size for the propellers at that voltage was 7x3 but I couldn't find ones that size, so using my minimal knowledge of propellers, I just went with that.
 
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So I'm not actually running 3S, it's just that that's the only battery I have that's working right now. I plan on using a 4S battery, with a 4-in-one ESC with 40 amps per channel. Currently, I plan on using a tri-blade propeller that is 7x3.5x3, but I'm not entirely sure if that is going to work. The recomended size for the propellers at that voltage was 7x3 but I couldn't find ones that size, so using my minimal knowledge of propellers, I just went with that.

I think if your camera is running off Vbat (that is battery voltage) you'll blow that camera with a 4s battery. It has a max rating of 12volts, and 4s is 14.8 volts. That means we'll need to find a power source from the FC before you go 4s

What's the size of those motors? (should be a 4 digit number like 2208) 1120kv is low for 4s 7 inch, but I think it should fly... There are better builders on this site I can run those numbers by.
 
So the way I set up the camera is that it has a dedicated battery and not running anything through the flight controller, I did this because I do not really need the camera and may move it later, and do not have an OSD system, so that should be fine. I know it's a waste of weight but the only real reason I have it is for documentation of flights (because the end goal is to have it all autonomous anyway).

The motors are 2836, and they are made by DYS, they have 1130 grams of thrust at max. throttle according to its spec chart.

Thanks again.
 
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So are you saying that I should spin a larger prop? And if so, what size would you/your friend recommend?
 
So are you saying that I should spin a larger prop? And if so, what size would you/your friend recommend?

Nope, I was wrong, I found that spec sheet you mentioned. I think the number just threw me.
I've run 1500kv on 4s with a 6 inch prop and it had plenty of get up and go. 1120 on 7" should be very efficient.

You have your ESCs picked out yet?

 
So, for connecting a Radio Receiver to the APM, would I need a uBEC to power the servo rail or should I just try to use an external battery?
 
I do not have a working multi-meter, but I do believe the outputs can provide 5V, however, in the wiring diagrams it says to connect the receiver to the input channels.
 
I've never used these servo cables, I run wires to solder points.
A multimeter is pretty cheap at the hardware store, you're going to want one before you're through. The diagrams that I'm finding aren't real helpful, but heres what we're looking at

OZ3ST56.png
 

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