I have a G-45 that is very sensitive just off of idle. My Eclipse does not have throttle curve capability. Does anyone know of an electronic throttle curve device that could be put on the throttle servo to allow a throttle curve to be set?

Thanks

Don

Your resolution is more than likely the problem.

Put a larger throttle arm on the engine and a smaller one on the servo. Then make it so your end points are both above 100% and within 10% of eachother. Will fix your problem. I almost never use a throttle curve regardless of the engine.

You could try changing your linkage mechanically to make it less sensitive off idle.

Ditto what Jake and w8ye said. To get the throttle curve with the servo you make it so at low throttle the servo arm is moving more across the plane than for and aft, that way you get lots of servo rotation with little throttle movement, then you get a lot of throttle movement as the arm is moving forward. The low speed is critical on the throttle, from 2/3 to full is much less so.

Thanks for the input fellas. I have set my linkage so that it is soft off of idle. But, with the servo arm almost parallel to the linkage I get very little idle speed adjustment capability. With it set up like that it is very manageable just off idle, but to have to adjust the linkage to set the idle is not manageable at the field. I feel that somewhere there is an electronics wizard that can give me a throttle curve or expo. Otherwise I'll just have to be cool on the throttle when landing.

Thanks

Don

If you have one of the high end radios more than likely it has such a capability.

Karol

My Futaba 9 CAP does.

He stated that he had an eclipse.

Kevin

Oops .... I missed that []

Karol

Parallel to the link has nothing to do with it. If your resolution is poor you can spend all day putting it in different positions. The problem is your resolution plain and simple.

You only need a throttle curve if you have poor geometry or a peaky pipe (thats a whole other story - can be adjusted differnetly). Spend some time fixing that and a throttle curve isn't as magical as it may seem.

The correct answer is in my original post on the topic - Longer arm on the carb and shorter arm on the servo, end points both 100% or better and pref. within 10% of eachother.


Edit:

ReReading this I am not understanding your reference to being parallel? Can't you just open the hole in the firewall to allow for some side to side movement? A picture would be worth....

Not ever having owned a radio with this sort of capability ( pity Futaba thought it better not to include it in their 8UAF model ) I learned some time ago that the length of carb and servo horns used made all the difference, and with some expo thrown in for good measure one could end up with a fairly linear throttle curve.

Karol

I have a DL-50 on a Comp-ARF Extra 2X2m that weighs in at 13.5 lbs. I had to get a little creative with my throttle setup as the Spektrum DX7 does not have throttle curve capability in Airplane mode. The Extra was a little tough to hover since the engine makes about 30 lbs of thrust and so accordingly very little throttle change makes for somewhat big changes in thrust output. I did wind up doubling the length of the arm on the carb for better resolution and also setting the servo arm up so as to get very little movement of the carb for the initial portion of the travel. Works pretty good now.

Hi Guys, this is what is included in my setup instrutions for gas engines for the "Twinsync". If you don't have a computer radio,,,this will slow down the rate of RPM acceleration for any engine. Rick

this picture says it all, and what Jack Rudy said in post #10

With the right geometry, you can make the linkage behave as though you are using the EXPO function when you are not. You will have to experiment a little but it is not too hard to figure out once you play with the different arm angles and pushrod length.

I'm not real old, but back in the day before computer radios, you had to be creative Some here know what I'm talking about.......


Mike

You are so very right about that. Unfortunately with the advent of computer radios with all the bells and whistles, some of us have either forgotten the basics or have just gotten lazy. While some of the the newcomers to our hobby have never a chance to learn some of the basics.

Karol

Hmmm..
I still know how to make an escapement to operate multi functions from a single on-off radio channel. You needed a quick finger and an organised mind on that pushbutton to get it goin' right!