Timinatorg
New member
Has this tx/rx combo worked together before? Not all receivers work with all transmitters. I've had problems myself with this. I found this chart that may be helpful.
Flysky Help Needed
- Thread starter wdiamond
- Start date
I was confused and thought ibus was a protocol used between an rx and a servo. I did read that hitec servos have a proprietary signaling from the rx to the servo, and that could leave me with a rx that does not know how to communicate with the servos I have. am not sure what a flight controller is or does.s
FDS
Elite member
Flight controllers are for automation, gps, gyros and are used in quads to control cameras, video, motors etc.
I would still buy some basic servos, 5-9g cheap ones, then see if they work.
Receivers that only need to talk to a flight controller use different signals to those that talk to servos, a servo is basically a motor. PWM is Pulse Width Modulation, a signal sent to the servo, which the flight controller wouldn’t usually read. Any receiver with servo plugs will be some form of PWM.
I would still buy some basic servos, 5-9g cheap ones, then see if they work.
Receivers that only need to talk to a flight controller use different signals to those that talk to servos, a servo is basically a motor. PWM is Pulse Width Modulation, a signal sent to the servo, which the flight controller wouldn’t usually read. Any receiver with servo plugs will be some form of PWM.
PWM stand for pulse width modulation, the Rx sends a signal to the servo, the signal is either on or off, it’s the length of time (the width of the pulse) how long it’s on that the servo interpreters. With PWM you need a separate signal wire for each channel. With everything else (ibus, sbus ppm and others) you send all the channels on one signal wire.
Keep in mind, with the 3 servo wire, red is always positive, the darkest color (black or brown) is negative, the lightest color (white or yellow) is the signal wire. The modern convention is to always have the red (positive) wire in the center. If you put the plug in upside down nothing bad happens. Some older servos had the red wire on the end. If you put the plug in upside down, you would let the smoke out.
Here is a more detailed discussion of PWM. https://en.m.wikipedia.org/wiki/Servo_control
Keep in mind, with the 3 servo wire, red is always positive, the darkest color (black or brown) is negative, the lightest color (white or yellow) is the signal wire. The modern convention is to always have the red (positive) wire in the center. If you put the plug in upside down nothing bad happens. Some older servos had the red wire on the end. If you put the plug in upside down, you would let the smoke out.
Here is a more detailed discussion of PWM. https://en.m.wikipedia.org/wiki/Servo_control
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I got new servos today and still got the brown out chirping servos w/ blinking rx light with the servo plugged into the rx. I did find out that when I take out the positive lead from the servo and hook that positive lead to a 9v battery positive and ground the 9v negative with a negative servo lead that is plugged into the rx....things work, only sharing the 9v positive lead with another servo's positive lead I can get two servos up and running. The problem I have now is that adding a third servo's lead (with the other two) to the 9v. positive lead, none of the three servos function.
The 9v power supply is just a 9v battery, though, and I am hoping that when I get the new rechargeable 7.4 battery pack early next week, I will be able to power up the four servos that I need for my gas plane.
Does this sound right? Can anyone help me understand why things work when I don't try to power the servos through the rx. Plus, has anyone set up their servos this way? Does anyone have a tip on how I should hook up four servo positive leads to one rechargeable lead from the new battery. Is what I am thinking of doing prone to fail? Will things heat up beyond a safe operating temp? Could I end up starting a fire on board the plane and possibly have a flying bomb from the fuel, if it gets too hot or is exposed to sparks or flame from four servos connecting to one positive battery lead?
Thanks again for helping. I do really need the assistance and am very appreciative of your time and experience.
kilroy07
Legendary member
Here's what I learned awhile ago;
https://forum.flitetest.com/index.php?threads/are-escs-consumable-items.53742/
https://forum.flitetest.com/index.php?threads/are-escs-consumable-items.53742/
A picture of your setup could help us diagnose the problem.
Hai-Lee
Old and Bold RC PILOT
I am confused here!
Most servos are designed to operate from 5 (FIVE) volts unless labelled and sold as a high voltage servo. Your use of a 8 Volt battery is greatly concerning BUT a small 9Volt battery cannot supply a lot of current and that may be why 3 servos won't work as it could be almost shorting out the 9 Volt battery.
I need a pic of your set up please as the way you are connecting the servos for testing is wrong. In addition IF you are using the smae 9V battery into the ESC to test the Rx then you can be assured it will never work properly.
have fun!
Timinatorg
New member
Hai-Lee is correct (as usual) 9V is more than the receiver was designed for, and so is 7.4V. Assuming it's a 2S LiPo battery, it's meant to power a motor not a receiver. Your test did however seem to verify that the receiver works which means you have a power issue when your 4AA pack is connected. I would suggest checking for voltage under load by plugging in your 4AA pack and one or more servos and see if you have about 5V on any unused servo pins in the receiver (center pins are + right pins are -). If voltage is low you probably have corrosion somewhere in the wiring or connector of the 4AA pack. You could also try plugging the battery pack into another slot in the receiver, all of the positive and negative pins are connected internally so plugging the battery into any of them will power the receiver and servos. This will show if the problem is in the receiver. Back in the day a 4.8V receiver pack was the norm to power a receiver and several standard size servos in a nitro plane so I don't think a higher voltage pack is the answer to your problem, it may end up frying your receiver or servos.
I wanted to let everyone know that I got a 6.0v (not a 7.4 as I wrongly reported earlier) that is rated 1600mAh and is not NiCad... it is NiMH. Once I plugged the new battery into the rx, one after another of the servos I had sprung to life and all were properly plugged into the rx (all three wires).
The 4 battery NiCad set-up just wasn't enough power. I have things working the way they are supposed to.....let's just hope I can keep it that way after the maiden voyage. You all rock. Thanks.
I will take some pics and post them after I get it in the air.....and back down in one piece.
The 4 battery NiCad set-up just wasn't enough power. I have things working the way they are supposed to.....let's just hope I can keep it that way after the maiden voyage. You all rock. Thanks.
I will take some pics and post them after I get it in the air.....and back down in one piece.
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