StPeteFlyer

On a spectrum radio is the travel adjust settings the same as ATV? I have read alot that ATV should be set at 140 for best resolution, but after going through my programing all I can find is travel adjust. If it is the same do I put both the low and high at 140 and then adjust my servo arm from there?

Thanks

BarracudaHockey

My Feedback: (11)

EPA = end point adjustment
ATV = adjustable travel volume
End points

All different ways of saying the same thing.

AWorrest

My Feedback: (5)

If you are not going to use the channel trim, set the sub trim or mix anything into the channel, you are correct in thinking the maximum travel will give maximum resolution. However you will need the overhead at the each end of the 100% travel if you do use the trim, sub trim or mix anything into it. Look at your monitor menu to see how these affect the total travel.

Allan

alan0899

G'day Allan,
Be aware subtrim sets the centre of the servo travel, ATV, EPA, end points, whatever it is called, sets each end of the servo travel.
In the DX7 servo travel can be set, up to 150%.

AWorrest

My Feedback: (5)

Alan0899,

I agree if there is a reserve of unused travel. But if you set your center by the sub trim to an extreme, such as aileron channel to the maximum left amount. And then set the left aileron travel to 150%, the aileron will deflect only a certain distance no manner how far you deflect the stick to the left. I run into this situation constantly when setting up flap deflection on a sailplane. There is a certain max and min value in terms of milliseconds that each channel can use. I'm sorry that I can't give the exact values for the DX7 as I sold my unit yesterday after I bought a X9303.

Allan

alan0899

G'day Al.
Subtrim is used to set the CENTRE, in other words, where the servo will stop, when you release the stick, if you use it for anything else, like for the extreme end of the servo travel, that is where you servo centre is, & so it will only move the other way, because your CENTRE is now at the extreme end of the servo's mechanical travel.
You set the centre with subtrim, & the amount in each direction, with end point.
If you need more one way than the other, reduce the end point of that direction, if you need more down in your elevator, then set the end point to 100% for the down direction & 50, 60, 70, 80, or whatever, for the up direction, but don't use subtrim to do that. it will only stuff you servo's centre point.

AWorrest

My Feedback: (5)

I think we have a common understanding but expressing it differently. It is not only a case of reaching a servo mechical stop which is usually more than the transmitter will support, but the JR transmitter channels also has travel limits that can't be exceeded. My reply to StPeteFlyer was to say that if you set the travel adjustment to the max, then you can't add in other factors such as other channel mixes or sub trims that will make the travel go beyond those limits. In other words the sevo will stop, not because it hits a mechanical stop; but because the transmitter will not transmit the extreme stick position plus the other stuff added in.

Allan

alan0899

G'day Al,
The endpoints set the amount of travel a servo has, any sort of mix, or trim, does nothing to that amount of travel, a mix simply means that another channel, works with that master channel, it does not reduce the amount the main servo will move.
Stick trim, or flight trim adjusts the point at which the servo stops, when the sticks are released, when flying, subtrim does a similar thing, but while you are setting up the plane, so that you can get equal travel, mechanically in both directions.

A.T.

E.P.A - A.T.V - Dual Rates differences, cautions and arming ESC
Regards
Alan T.
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