Gyro gain values.

OK so I've just replaced the Align gyro on my 450 pro with the new Spartan Quark and a 9257 tail servo when I noticed something interesting that applies to all gyros.
The gain setting on different controllers is very different for example,
Futaba using the gyro menu if you put in 30% gain then it gives you 30% true gyro gain.
JR/Spektrum if you use the gear channel travel adjust 30% gives you 20.8%.
So what you see is not the true gain value for JR/Spektrum.
Here's the formula I've found online.
JR/Spektrum if using the gear channel take the number and divide it by 1.44.
If using the gyro menu then take the number and minus it by 50 then multiply that number by 1.44.
I hovered it for the first time yesterday and needed 29% on gear which is 20.1% true gain which is too low so I've moved the ball link in to 7.5mm from 8.5mm which should allow the gain to go a bit higher.
To summarise,
gear value /1.44=true gain.
Gyro value-50 x 1.44=True gain.
Sorry if this is boring thread,I just like to share these things.
Danny.

Hi Danny, not sure whats going on there as the gear channel should give you linear gain using if memory serves a possitive value for normal and a negative value for heading hold.
This assumes the gain is set using the throttle ATV.
Problems occur when you use the gyro sense in auto mode whem then 0 to 50 will be heading hold and 50 tro 100 is normal mode.
For a required gain of say 25%/normal mode you would set a possitve value of 25% if using the gear ATV or 62.5.% if using auto gyro sense.

Think of it this way, In auto gyro sense mode you have 50 increments above 50 which equate to 0 to 100 %gain or 2%gain per increment.
The same below 50 for Heading hold.

I always set a heli up using the gear channel to adjust the gain then when happy transfer to the gyro menue as this means you can have gain set for each flight mode.

As Andy is fond of saying I could draw it easier than explain it. Perhaps he will lend me his white board some time

Good fun these helicopters

DaveS

A whiteboard? Pah! I only work with blackboards and chalk for explaining things, none of these new fangled whiteboard rubbish! Oh, you are welcome to borrow it too.....

I thought it was all irrelevant anywAy, when it comes to gyro gains, is it not just a case of adjusting it until it is behaving how you want, and leaving it there?

Andy

Hya mate,what I mean is that as the gear channels endpoints go from -150 to +150 with the +150% set then the gyro will be at 100%.
Basically on my 450 it has been that about 30% seems to be optimum and I've now discovered that 30% on my gear channel has not been true gain,it has been around 20% true gain and according to spartan if your gain is less than 35% true gain then you need to go in a bit on the servo horn link.
Here's a good link,about halfway down the page there is a video post by Finnless going into detail on different radios.
http://www.helifreak.com/showthread.php?t=176987&page=16
And this is the instructions from the website with a chart for different radios.Checkout page 15.
http://www.spartan-rc.com/products/quark/userguide/index.html
Quite interesting stuff.

I just give um Dave and get them back when they work

All gobbeldy gooch to me TBH