Servo interactions

[cjcj1949]

Subtrim and trim do the same function on my DX7 at the moment. 20 units of subtrim is about 10 clicks of trim. I was waiting to fly at the time and I just did it by eye.(Converting trim to subtrim) I was not expecting two servos to move with aileron sub trim. But the subtrim menu I have goes by function rather than than channel. I think it's confusing when servos that carry out multiple flight functions are named by function rather than by channel. It is a 120 degree swash plate, a DX7 and a AR6100E rx from a CX2. Perhaps there's a subtrim control function somewhere that I've deactivated.

[scallybert]

Subtrim and trim do the same function on my DX7 at the moment. 20 units of subtrim is about 10 clicks of trim. I was waiting to fly at the time and I just did it by eye.(Converting trim to subtrim) I was not expecting two servos to move with aileron sub trim. But the subtrim menu I have goes by function rather than than channel. I think it's confusing when servos that carry out multiple flight functions are named by function rather than by channel. It is a 120 degree swash plate, a DX7 and a AR6100E rx from a CX2. Perhaps there's a subtrim control function somewhere that I've deactivated.

That is bizarre.

I've just played with a DX7, looking at the monitor, and the sub-trim on that is definitely per-servo.

ie I can independantly get aile, elev & pitch monitor displays to zero, using sub-trim. one sub-trim does not affect other channels.

[cjcj1949]

I've just done 7 6 minute flights and the heli behaves perfectly driven by the DX7. I also flew inverted for a bit which I haven't done before. I'll investigate the monitor screen. I'm not that bothered though as I'll be moving over to my Multiplex Cockpit as the range on my AR6100E is now down to 20 yds. It was 45 yds last time I checked. I can now fly the heli far enough away for range to be a possible problem. The range checks were very strange. We are very close to a road taken by large lorries. Usually when one went passed when close to the range limit, the reception would go but not come back. 2.4G range seems very variable, possibly only when close to the ground. I had no full power loss of control at up to 50yds.

[cjcj1949]

Well we all talk b*llocks from time to time and I was not sure who was guilty. That's guilty in a light hearted sense. I wondered if there was a different version of software on my DX7. I rechecked the current model memory and it did as I said. Subtrim controls function not servo. I then tried another memory set up as a heli and that behaved the same. Subtrim controls function. I then investigated further and found in the first menu where you specify swash type that the swash was entered as 1 servo and not 3 servo 120. So this was even stranger as I shouldn't have had a swash mix option and subtrim should have controlled each servo as it is one servo per function. I reset this memory, set up 120 swash and checked subtrim again. Now it works as you and everybody else says. Subtrim controls servo as it should.

I've looked on the memory that had subtrim controlling function and the actual servo positions are wrong. They are in the centre at min throttle wheras they should be at minimum. Perhaps like Eric I have pressed the right keys but not necessarily in the right order, or the memory has become corrupted. I will make a note of all settings, reset and try again. Subtrim is the correct thing to do. Thanks for putting me one that path of truth.

[scallybert]

(Eric) Morecombe.

It's weird what software can get up to.

[cjcj1949]

Especially the stuff I used to write. I think people using leading edge stuff are very brave.

[cjcj1949]

I've corrected the subtrim programming problem by copying the model to a new model memory and then copying it back. Most of the time was spent making a note of all the settings. I didn't need them. The subtrim now does what it should. It only changes one servo at a time. Very strange, but at least it now works as everybody else says, and it makes sense. I can now adjust the servos to right angles at 0 pitch, one at a time.