Servo End Point Adjustment
03-15-2006, 07:01 AM
#2
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RE: Servo End Point Adjustment
I think you get greater mechanical leverage with higher EPA at a very slight speed penalty. When using dual rates I prefer the low rate setting to be under 100%.
An EPA under 50% is very taxing on the servos.
Bill
An EPA under 50% is very taxing on the servos.
Bill
03-15-2006, 12:09 PM
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RE: Servo End Point Adjustment
I adjust mine all the way out till they stop the control surface and then back it up just a bit. Then just use the dual rates to set my flying style. I just answered this question... LOL
LATEr
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03-15-2006, 04:41 PM
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RE: Servo End Point Adjustment
you want your epa to be around 100. It will function all the way out. The problem is you loose linear control of the servo. If you set your epa to 120 on both sides and slowly move the stick back and forth you'll notice at some point the servo moves faster. kinda like you added expo. this is becuase the signal is not recaluculated across the entire range. At least it does that on mY 6XA and 7CAP
03-16-2006, 04:52 AM
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RE: Servo End Point Adjustment
"The problem is you loose linear control of the servo. ... not recalculated across entire range..." -????
I'm having a hard time buying that since I've never seen what you described on my equipment. Maybe you need to recalibrate the sticks on the radio? Or maybe the pots in the servo are screwy? Besides, while the stick movement may translate to some linear coded position, the output on a radial arm servo is anything but linear even at 100/100 ATVs (EPAs, etc.) You will naturally get "bad" expo because of the radial to linear mechanical translation between the servo arm and control horn. It takes about 20% expo (- on futaba, + on JR) on most radios just to get things back to linear. If you are way off balance, like 80% ATV on one side and 120% ATV on the other (not a suggested setup), the servo will have different angular speeds on each side of neutral. Maybe you could explain in more detail what you saw?
Some cautions... if you over drive, be aware that some servos max out their throw before your endpoint adjustment is exhausted on the radio. I've seen several servos that stop moving past ~120% with Futaba 9ZAP TX. As long as the servo didn't hit a hard stop, this probably doesn't hurt the servo, but it isn't doing you any good either to over drive if the servo past what it can move too. Also, if you use mixes, depending upon your radio and how you set your endpoints, you can end up with no mix headroom at full deflection because you used up all throw in the ATV. IF your radio supports AFR, you can ensure you will have headroom by setting ATV to limit and then dropping the AFR below the ATV rate. You could also do something similar with rates, i.e. set high rate a bit below 100% to gain what is needed in headroom, etc.
I'm having a hard time buying that since I've never seen what you described on my equipment. Maybe you need to recalibrate the sticks on the radio? Or maybe the pots in the servo are screwy? Besides, while the stick movement may translate to some linear coded position, the output on a radial arm servo is anything but linear even at 100/100 ATVs (EPAs, etc.) You will naturally get "bad" expo because of the radial to linear mechanical translation between the servo arm and control horn. It takes about 20% expo (- on futaba, + on JR) on most radios just to get things back to linear. If you are way off balance, like 80% ATV on one side and 120% ATV on the other (not a suggested setup), the servo will have different angular speeds on each side of neutral. Maybe you could explain in more detail what you saw?
Some cautions... if you over drive, be aware that some servos max out their throw before your endpoint adjustment is exhausted on the radio. I've seen several servos that stop moving past ~120% with Futaba 9ZAP TX. As long as the servo didn't hit a hard stop, this probably doesn't hurt the servo, but it isn't doing you any good either to over drive if the servo past what it can move too. Also, if you use mixes, depending upon your radio and how you set your endpoints, you can end up with no mix headroom at full deflection because you used up all throw in the ATV. IF your radio supports AFR, you can ensure you will have headroom by setting ATV to limit and then dropping the AFR below the ATV rate. You could also do something similar with rates, i.e. set high rate a bit below 100% to gain what is needed in headroom, etc.
