Control RC transmitter switch with Arduino?

Hi Im new to Arduino. Im trying to hook up an Arduino to a RC transmitter to control an RC blimp motor. The RC controls are digital basically on or off, when you press the button you basically close the circuit. I am not sure if this can be controlled through the arduino. I know some people use solenoids to do that to physically press the switch. But since there are 6 buttons it would be too many solenoids, in addition from what i understand solenoids nees special wiring so they dont damage the arduino and they can overheat and get damaged. Any feedback would be incredible. Thanks for any help/ideas.


You can probably use a 4066 or quad analog switch to do this.

This IC has 4 pins that work as control pins, and 4 pairs of pins that work as switches. When you apply 5 volt to a controlpin the corresponding switch pin pair closes like a switch.

You would need two of these IC's to control 6 switches (well 1½ really :-) ).

You would connect 6 digital pinns on the Arduini to 6 of the control pins on the two 4066 IC's, and the 6 switch pin pairs to the each side of the 6 switchws in the RC transmitter.

For a more detailed example check this page on my web site: I shows how to switch stuff with the parallel port on a PC, but the principle is the same using Arduino.


EDIT: Its important to remember that the voltage you switch with the switchpin pairs on the 4066 can not exceed the supply voltage to the 4066 IC, or it will fry.

Thanks so much for the reply ;D

I will try this immediately - well as soon as i can get the 4066. Im not sure about the last comment about frying the IC. The transmitter is powered by a 9V battery thats basically all I know. Would that be ok?

also do you have any recommendations on where to get the 4066. ?

Thanks a ton.

You might want to look at using opto-couplers also...


I can't comment on what you want to do, but I am curious whether you str connecting Arduino directly to your TX or to the RX in the blimp?


the transmitter i want to run the arduino using max.

You can get the 4066 IC in any electronics store. It is very common and very cheap. You could use the 4016 IC as well it is identical, except for some minor differences in the internal resistance of the switches.

You can run it from a 9 V supply voltage, as long as the voltage across the two points in the RC transmitter you are switching do not exceed 9 V. This is not likely to be a problem in your case, as i assume the 9V battery is the only source of supply voltage in the transmitter, and therefor there will be no voltages over 9V in the circuit.

thanks a lot i will go and look for it.


optocouplers are a very good solution to this kind of thing ase you keep the Arduino power supply separate from the RC power supply. You can figure out the polarity of the switch by putting a 1N914/4148 diode across it. Once you have that a info, you just hook up the optocoupler's transistor to the switch, and drive the input side as you would an LED with the Arudino. The advantage here is that you get noise, RF and voltage isolation between the two devices.


thanks a lot for you reply! any idea if optocouplers are available at radioshack?



try digikey or jameco...


Thanks guys I got it to work pretty easily with the optocouplers it took a little trial and error, i didnt know how to use the diode to figure out the polarity. Also i didnt know that i had to put the optocoupler in the middle of the breadboard where it isolates input and output... but all is good too bad im not really proceeding with this project...