desertbird

iTrader: (7)

Not trying to start an argument Jaz, but actually, expo has nothing to do with the speed of the servo arm, it's controlling the amount of throw per a given amount of stick input. It may be perceived as speed, but it is not.

A servo that is being controlled with -50% expo vs. the one with 0% expo will both hit the EPA at exactly the same time. The one with 0% is on a linear curve so at half stick input, or with the stick at mid point (imagine an airplane radio) the throw on the servo horn will be half way. It's a one to one relationship. The one with -50% expo will be less than half way on the servo horn with 50% stick input.

Look at it like this:

Stick input, Throw w/0%, Throw w/ -50%
10%, 10%, 2%
25%, 25%, 10%
50%, 50%, 25%
75%, 75%, 70%
90%, 90%, 89%
100%, 100%, 100%

Expo dials out throw around the center point of the wheel, it does not change the transit speed of the servo arm.

Jaz240

iTrader: (52)

yes. You are correct..Its just easier to explain in terms of speed, as you turn your radio wheel, or pull the trigger. It will not get your wheels to full throw at 1/4 turn from your radio, or your throttle to WO at 1/2 trigger..I guess speed is a bad way to explain it...trying to make it as simple as possible..Thanks for the correction

markr04

iTrader: (1)

I use exponential on my throttle. I had an 8ight RTR and the engine (Mach 427) was a bit of a monster. Power seemed to be non-linear without using exponential - it felt as if 50% throttle squeeze was more like 90% engine output.

Exponential on the throttle allowed me to keep it under control as if it were a more average .21. And now I'm just more accustomed to using it, even though I no longer use that engine.

Sam-E

iTrader: (3)

Not trying to bust your balls Jaz my man but yep expo has nothing to do with the speed of the servo... good to see you keeping it simple though.

p.s. The Drake aka Dan Drake has taught me well!!!

ridein04

iTrader: (15)

excellent explanation Desertbird

Jaz240

iTrader: (52)

Damn Its Dan! I Thought it was Don!..I've been telling people the wrong name...every time someone attacks you for bringing up "The Drake" I been telling them its Don..after they squirm a little first....

Now everyone pay attention because I have been thinking..(can you smell the calamari Burning)

Throttle servo with positive Expo, negative expo, and No expo..same servo

you pull the trigger..how quickly it gets to WOT is all relevant to the expo setting as the bigger the curve, the more you have to pull the trigger to reach WOT..... taking more time!!! I win

Sam-E

iTrader: (3)

It actually reached WOT at the same time it just took less trigger movement to get there!!

jewn_beef

iTrader: (30)

he is new to hobby it seems so lets keep it simple no dual rate no expo what he needs to do is set his epas how is easy turn your car and radio on then turn wheel on radio all the way to one side then adjust the epa per the radio manual until the wheels hit full turn at the same time the servo horn hits full movement
meaning if you look at your servo horn moving if it is still moving when wheels are at full turn you need to turn down your epa if at full turn you can still move wheels to turn side more you need to turn your epa up. dont for get to do both sides. also take air filter off motor and set throttle epa so that the carb inner slide just gets to full throttle if dont set it will ruin carb and servo