Simple RF T4 Receiver - 315MHz Toggle Type

[indianlake]

I have the RF T4 receiver connected to an arduino which controls a servo motor. Why is it that everything works as long as the arduino, which is powering the RF receiver, and the servo are connected to separate power supplies? Once I try to connect the arduino, the RF Receiver, and the servo to the same power supply the Reciever begins to not work properly. The servo behaves erratically and the RF Receiver will no longer work? Is there a way to run everything off one power supply and still have everything work properly? I am only using one tiny micro servo with no load on it so power is not an issue. There seems to be some sort of interference going on with the servo motor and the RF Receiver. I have tested it with serval different brand servos. All do the same thing. Please help.

Thanks,

Jared

[paulf8080]

That type of question is by far the most discussed by engineers, in my opinion. It's noise on the ground. Fixing it is an art, I guess. I guessed using a ferrite bead on the servo wires. Google brings up a lot of for/against ferrite beads in the RC forums. Good luck.

[adafruit_support_bill]

It could be noise on the ground, noise on the 5v bus, and/or simply voltage drops due to current spikes in the servo operation.
Noise remedies include, ferrite beads on the ground leads, capacitors on the servo motor, or simply moving to a higher-quality servo.
Voltage drop remedies may include a stronger power supply, better wiring, BFC between power and ground.

If you post a photo of your setup we may be able to suggest some alternatives.

[indianlake]

Attached is a photo showing the setup I have. Connections... 1. The servo motor is connected to an adafruit motor shield. The servo is being supplied via separate leads with 6V, since I cut the wire on the motor shield board that originally only supplied 5 volts. 2. The RF Receiver is connected to ground, 5V, Pin 12 and 13 via the motor shield through the arduino board underneath. The arduino is being supplied 6 volts with separate leads via the same 6 volt battery. With this configuration once turned on the servo motor begins to move in short incremental steps and then just stops. The RF Receiver doesn't work properly. If you disconnect either of the power supplies and connect one of them to a separate power supply then the receiver works and the servo runs the program correctly. (Note: I have wired this up without the motor shield to a bread board and the exact same thing occurs)

Question... Is there anyway to wire this up differently so that only one power supply is needed, because I am trying to wrap up a project and it would be nice to just have to have one power supply with one on/off switch instead of having two power supplies and two on/off switches?

[indianlake]

Update. I connected a 9 volt battery pack of AA batteries and this time soldered them such that all connections were better and now everything seems to be working just fine with only one power supply.

[indianlake]

Update #2. Well having better connections worked when connected to a small servo. Once connected to a larger servo the servo would run the program, but the remote would only sometime work and the remote would have to be really close to the receiver. Once two power supplies were installed again, now remote works from a far distance again.

Question, if I had a better battery source would it be possible then to only have one power source? Or is there a possible grounding issue?

[Franklin97355]

One thing you can try is take all your grounds, tie them together and connect them directly to the battery terminal.

[adafruit_support_bill]

Sounds like you had a combination of voltage drops and noise. The better battery pack fixed the voltage drop problem, but it sounds like you are still getting servo noise coupled through the servo cable. Ferrite rings might help with that. These are commonly used to suppress servo noise that interferes with RC receivers and are available form many hobby-shops specializing in RC gear.

http://www.rchelination.com/ferrite-rin ... -use-them/