electronf

I presume that I will need to plug a speed controller into my freedom flyer in order to control the speed however I was wondering if anyone new if I would be able to modify the existing three channel controller (engine on-off switch) to be able to control the speed as well or do I need to buy a new controller?

I have heaps of electronics experience bt I don't know much about RC controllers.

Matt Kirsch

My Feedback: (21)

Knowing the typical way these planes are constructed, I'm afraid that you'll probably need to rip the receiver out and replace it with more conventional R/C gear. The servos are standard GWS "Pico" or lookalikes from the pictures I've seen; as long as they have three wires you can add standard connectors and connect them to a standard receiver. Heck, they might have the correct connectors on them already. Make sure the red wire is in the middle.

electronf

Well, one of my friends with a Freedom Flyer swapped the crystal across to his Futaba full 4ch radio and hey presto, the speed control controls the speed of the engine....WITH NO MODIFICATIONS NECESSARY.

The only thing he had to do was get the right controller channels talking to the right reciever channels so that his control setup was normal. Took all of about 10 minutes.

The only thing left to do now is see wether the stock radio controller can be modified for speed control rather than just on-off...

Looks like the FF does have a speed controller.

More updates later.

cjalphonso

So your saying if I bought a Hitec Flash 5X and used the crystal from the freedom flyer I would then have speed control? I don't know much about this stuff, but I own a freedom flyer and was thinking about buying the Hitec Flash 5X to possibly use with a slow stick.

electronf

Well I can't say categorically because I don't know that much about controllers but from what I know I would presume that that is the case.

electronf

Well I have taken the controller apart and tried a potentiometer in conjunction with the on-off switch and here is what I found:

The controller is capable of being modified so that you can control engine speed.

There are two wires going to the on-off switch. I originally thought that if I just sonnected a variable resistor inline with the switch that that would do the trick, however the way it works is opposite to what I expected. When the switch is closed (ie there is no resistance) the engine is cut off.

I then found that the higher the resistance, the higher the engine speed. Maximum engine speed is open circuit although I suspect that there is some amount of resistance at which you get maximum engine speed.

Unfortunately I only had a 100K variable resistor. It appears that at full resistance I am getting about half engine speed.

What I have done at the moment is connected the off side of the on-off switch to the variable resistor and then connected the other side of the resistor back to the wire that is connected to the other side of the switch. Of course this means that I can switch the engine off as per normal, but I only get about half speed as a maximum. I then installed a switch in line with the variable resistor so that I could pull that side of the circuit completely open thus giving full speed.

What I have now is two switches and a dial:

Switch 1: Engine On-Off as per the original design.
Dial: Engine speed from 0 up to about half speed.
Switch 2: Full Speed or Variable speed.

This allows me to switch the engine on. Switch the engine to full speed for launch and climb. Switch to 'cruise' or variable speed to cruise around.

This also makes landing in a particular location a bit easier because I can bring the plane in slowly without having to either switch the engine off at exactly the right moment, or switch the engine on and off if I am coming in too short.

Next step is to get a larger variable resistor, plus add a fixed resistor in line with the variable one in order to bring the minimum speed up from 0 and to increase the maximum speed. I will post again when I have done this.

electronf

Okay one last mod...

I added a 56k resistor in line with the variable resistor to bring the minimum resistance up. So now I have 56K plus 100K variable. Now the engine stops at almost full anti clockwise and is running at around 90% full clockwise.

I have wired all the parts in and mounted the dial and new switch on the top of the transmitter on the opposite side to the engine on-off switch.

Sweet.

Word of caution though, I would suggest two things:

Always launch with the Cruise/Full Power switch in the Full Power position.
Don't run the engine at low speed when it is on the ground as this may damage the engine.

I will post a circuit diagram and some pics as soon as I get a chance.