roffey
Dec 08, 2005, 05:41 AM
As a newbie I don't want to re invent the wheel, so I would like to ask the following.
I have a couple of co axial helis which suffer from local interference. (My hirobo does not, so it must be the rf section design). Anyway, all efforts have failed.
The solution would appear to be pcm. I have a dual controller, and have bought a futaba R146ip-35 to use. All goes well, until I I try and find out why I can't use it.
I need to use channels 3 & 4 for thrust and rudder. All well and good until I put these signals into the esc/gyro chip.
This chip needs a back to back packet data of thrust followed by rudder with no interval.ie. whatever the thrust does, the rudder signal must follow immediately, regardless of pulse width.
The pcm puts out concurrent 3 & 4 data.
I tried using channel 5 from the pcm, which is delayed from channel 3, but this does not work.
To prove the issue, I knocked up a simple analog circuit which generated the required channel 3 & 4 output. Shoving this into the the two thrust/rudder inputs of the esc worked fine.
Ideally I would just buy a compatible esc/gyro unit that would drive the helis, but these are just not there for co axial helis.
Firstly - is there a chip that will do this conversion ppm mimic already?
If not then I have to prog one up. I use ST chips and am comfortable with them due to path I have taken in my work life.
Obviously, pic chips seem to be everybodys favorite and might be a better way to go should anyone else wish to travel this path.
It would be interesting to hear alternative opinions.
I have a couple of co axial helis which suffer from local interference. (My hirobo does not, so it must be the rf section design). Anyway, all efforts have failed.
The solution would appear to be pcm. I have a dual controller, and have bought a futaba R146ip-35 to use. All goes well, until I I try and find out why I can't use it.
I need to use channels 3 & 4 for thrust and rudder. All well and good until I put these signals into the esc/gyro chip.
This chip needs a back to back packet data of thrust followed by rudder with no interval.ie. whatever the thrust does, the rudder signal must follow immediately, regardless of pulse width.
The pcm puts out concurrent 3 & 4 data.
I tried using channel 5 from the pcm, which is delayed from channel 3, but this does not work.
To prove the issue, I knocked up a simple analog circuit which generated the required channel 3 & 4 output. Shoving this into the the two thrust/rudder inputs of the esc worked fine.
Ideally I would just buy a compatible esc/gyro unit that would drive the helis, but these are just not there for co axial helis.
Firstly - is there a chip that will do this conversion ppm mimic already?
If not then I have to prog one up. I use ST chips and am comfortable with them due to path I have taken in my work life.
Obviously, pic chips seem to be everybodys favorite and might be a better way to go should anyone else wish to travel this path.
It would be interesting to hear alternative opinions.