Let's Make Robots!

RC receiver question

Hey LMR!

I need your help on this one: Above is the RC setup I'm planning to use in my next project. I extracted it from a wrecked RC plane I got my hands on. As you can see it's quite basic: a 4-channel receiver, speed controller + motor and servos. I know that each controller function corresponds to one of the four designated outputs on my receiver. You'll notice there's also another output port, labelled 6/B:

Does anyone know who to control its output from a standard four-channel transmitter? I just probed it with my multimeter's frequency counter and found that it outputs a steady 60Hz when the transmitter is on. Something tells me it has to do with those mysterious prefabricated mounting holes that I found:


Does this kind of transmitters have button and switch expansion capabilities? It would really help if I could turn this output on/off from my transmitter.

I eagerly await your responses !

EDIT: Here's a few pics of the inside:

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It would be helpful if you can show us detailed view of the internal PCB :) because that is what matters.

seems like an e-sky to me ?!

Yes it's an E-sky :-)

Ill get pics up in a moment


You can easily get to those channels... Just buy a 5 channel transmitter. Seriously, no --there is no easy way to "steal" an extra channel out of your tx/rx set up. The folks that make this RC equipment have found that it is cheaper to make just one multi-channel RX instead of a 4 ch, 5 ch, 6 ch etc. and they simply include the same receiver with all thier stuff. I personally have a 9 channel reciever talking to my 4 channel transmitter.

3 sticks and a throttle, that's all you get.


You might be right... but i've seen a number of tutorials about hacking-expanding RC transmitters. I still believe this is possible.

You could easily put a micro controller on the plane and have it decipher the pulses coming out of the reciever. Your options are without limit there --2 quick movements of one of the sticks could put it into "menu mode" then another stick could control the "options" within that menu mode --you could code whatever you want. And sure, there are certainly ways to hack the transmitter so it will output an "extra channel" worth of data when it sends. However, if you are a beginner, this is pretty major stuff here and 5 channel transmitters are cheap on ebay.

But since I'm not building a plane, and I only need 1 servo (therefore 1 free channel), I thought I'd rather use one of the other channels to toggle on/off. I'll just do this :

So that I can have the rudder channel output a HIGH or LOW  whenever I like.

If you are in the US, you CANNOT use an air based R/C package on a ground-based vehicle, which a robot would be considered.

6b may have an optional use. the B could signify that you can plug a small aux battery in that port. This could also be a mix port where it's not directly controlled by a specific input but controled by the amount of 1 other input(channel mixing) It's something that is used on heli's and rc cars for example. Heli's I believe it would be with the throttle mix to adjust the pitch of the rotor blade  as the throttle is increased. In rc cars the mixed channel could be used for 4 wheel steering. Of course....it could just be an extra channel that you can't use...  :) Check the manual if you can find it online....

I think, but I may be wrong, that these pins (B for Bat) are power takeoff for auxiliaries like landing lights etc.