Lack of detail in DX7 Manual

[zoomsan]

Maybe it's just me but I have not found anything in the DX7 Manual that explains in detail what exponetial, dual rate, auto dual rate expa, sawashplate mix % for aile, elev, pit funtctions do. I have read messages that say if your heli is too sensitive to try some expo but what does that mean. Is there a manual or book that explains in detail the nuts and bolts of theses functions and how they relate to modern 120 ccpm helis?

[TheBum]

The December 2007 issue of RC Heli magazine has a good 7-page article on setting up a DX7. You can order a back issue either in printed form from the rchelimag.com website or in electronic form at zinio.com (requires using the Zinio Reader application).

[ZipZap]

I don't know of a one-stop resource for all knowledge. Maybe if you ask one or two questions at a time, the folks here will help.

Exponential:

RC systems are "proportional", that is, servos move proportionately to stick inputs. The amount of servo movement for a given stick movement can be adjusted a number of ways. One of the ways is through an exponential setting. When the radio is at the default settings, servo movement is linear w/r/t stick movement. If full movement of the stick causes a 90 degree movement of the servo, then half stick is 45 degrees and quarter stick is 22.5 degrees servo movement. Exponential changes this relationship; it can either decrease, or increase, the sensitivity (movement) of the servo around center stick. Increasing (positive) exponential causes the servo to move less w/r/t the stick movement around center. So, even though full movement of the stick would still produce 90 degrees of servo movement, quarter stick might only produce 5 degrees of servo movement. Negative exponential does just the opposite. Quarter stick input might produce 40 degrees of servo movement.

Positive exponential is useful on a heli, especially during learning. It gives the flier a more "stable" feeling for hovering. However, using too much lessens control authority so much that it becomes counterproductive. I'm fairly new to heli's, I have a DX7, and I'm flying at -25% exponential on elevator and aileron. It is pretty comfortable to me.:thumbup:

[zoomsan]

Thank you gentlemen for the advice and information. The response on exponential was really good. I will experiment and see if my hovering becomes more stable.

[joehelicopter]

Thank you gentlemen for the advice and information. The response on exponential was really good. I will experiment and see if my hovering becomes more stable.
Follow Jermo's DX7 setup in the Helifrak Tech room.......:Bang:Bang

[ZipZap]

Thank you gentlemen for the advice and information. The response on exponential was really good. I will experiment and see if my hovering becomes more stable.

Thanks, although I see a mistake. I'm flying +25%:o