Originally Posted by kodak_jack

I've read posts on here where guys say you have to be a certain distance away from the MQX to bind it.

I have observed no minimum distance in hundreds of flights. Mine are usually just inches away when bound. Never have I bound a mQX while more than 10 feet away from my DX6i. On more than one occasion I have bound both of mine to the DX6i at the same time while they were both just inches away.

Originally Posted by kodak_jack

I've read posts on here where guys say you have to be a certain distance away from the MQX to bind it. What sense does that make? You turn on the transmitter and then walk 20 feet away to the quad to plug in the battery?

This is a comment about transmitters in general:
if a receiver is too close, the signal may be strong enough to overload the receiver so that receiver starts distorting the received signal.
Also, a transmitter also often sends some weak signals that stray from the main signal. When close enough to the transmitter, these strays may also get picked up by a receiver, confusing it (I have gotten this effect on 72Mhz).

Originally Posted by flying-llama

This is a comment about transmitters in general:
if a receiver is too close, the signal may be strong enough to overload the receiver so that receiver starts distorting the received signal.
Also, a transmitter also often sends some weak signals that stray from the main signal. When close enough to the transmitter, these strays may also get picked up by a receiver, confusing it (I have gotten this effect on 72Mhz).

72 Mhz on my first heli's by Esky was a curse! Nothing like the thing falling out of the sky and doing the chicken dance!! I have to agree with Larry that after the transmitter is turned on, you only have so much time to plug in the battery before the bind just doesn't happen. Like I've said, though, I've had to rebind my quad and transmitter 3 times in the short time I've owned it and the infrequent number of times I've flown it. This isn't with a cheapie stock game controller transmitter either.

I'm pretty sure I've seen it listed somewhere before as a suggestion from HH if you are having difficulty binding. I'm not sure the logic but I tried it because nothing else was working.

On my first mQx flight I had d/r set to 75% on low for all axis with step 2 and 3 set to 100% and 125%. I was amazed at how responsive it was at 75%, so much so that it only needed slight stick movements to fly circuits. I did turn them all up to 125% for a minute to test, and I was more amazed. Today I hope to find a nice big grassy field to test this out more.

No offense but I wish people would just be clear about expo, dual rate, and travel adjust on the DX6i.

Travel adjust (also called servo endpoint adjustment) can be set anywhere between 0 and 125% and determines the total travel of a servo. Or in the case of the mQX, the total range of adjustment in a channel.

Dual rate can be set anywhere between 0 and 100% independently for high and low and determines a relative value of how much of the servo travel is being used for the position. D/r cannot be more than 100%. Thus for example if servo travel is set at 125% and d/r is set at 50% the total available travel is 62.5% of what the servo is capable of.

Lastly, expo determines the shape of the curve between 0 and full travel. A value of 0 means it is a straight line (directly proportional). The higher the value the more bowl-shaped the curve is, meaning the initial travel movement has the least effect. It serves to "dumb down" the sticks near their 0% position and make them exponentially more effective towards full deflection. It does not change how far a servo travels, it only determines how it responds to stick movement.

If you want to determine how effective a servo is, use travel adjust. If you want to have two different settings of that, use dual rate with two different values. If you want to adjust how harsh a servo reacts to your stick movement use expo. That's it.

4x4rc, that's very well put. I've also noted in other forums comments made by people who use negative exponential travel, so they have extreme sensitivity near the center of the stick movement, slowing near the limits. It makes little sense to me to have such a configuration, but apparently those who use it are satisfied with the results.

Because the mQx and other multi-rotor aircraft do not have physical servos, can one set the travel adjust beyond 100 percent and effect a genuine difference? I would think that 100 percent is the electronic limit of the action for that channel and it would be impossible to go beyond that.

Just acquired one of these little guys tonight, used but in perfect order. Bound to my DX8, set all rates at 40% and put two batteries through it, in my living room and kitchen area.

I am an RC Plane guy, but this looks fun. Had a ball with it already. Looking forward to the indoor gym session I'm going to in 10 days time.

Originally Posted by 4x4rc

No offense but I wish people would just be clear about expo, dual rate, and travel adjust on the DX6i.

I think the problem comes when explaining how it works. To help that make sense, I like to talk about how it actually functions, mathematically, internally, with input and output of the radio. Your sticks and switches are the input, and channel positions are the output. End-point/travel adjustments affect the output channels, and expo and dual rate affect the input channels. We know this to be the case because on mixing setups such as CP helicopters, dual rate and expo affects multiple servos, while end-point adjustment affects individual servos. Sub-trim and trim are the same way - trim works on the stick, sub-trim works on the output channel.

Originally Posted by fred_dot_u

Because the mQx and other multi-rotor aircraft do not have physical servos, can one set the travel adjust beyond 100 percent and effect a genuine difference? I would think that 100 percent is the electronic limit of the action for that channel and it would be impossible to go beyond that.

Regardless of how it really works, increasing the rate will make the helicopter seem faster - even if it's ignoring everything above 100% - because the higher rate basically lets you move the stick to full (whatever that is) sooner. Your movements will affect the radio output more quickly.

4x4rc, thanks for the clarification. Over the winter, while not using the DX6i, I have a tendency to muddle the D/R and Expo definitions in my mind. Before I got the mQX the only indoor helis I had use their own OEM transmitters with no programability. Now the mQX will allow me to fly something year round with the DX6i, so hopefully those terms will remain clear to me.

I, too, would like to know if increasing travel adjust beyond 100% on the mQX is really doing anything. Perhaps it is, based upon how the controller interprets the incoming commands from the TX, but it isn't like being able to measure a servo arm travel. I am wondering if an optical tachometer used on one of the motor shafts could measure the actual result of setting travel beyond 100%? If the props were removed this could easily be tested on a bench. The tiny motor shaft diameter might be an issue though. Might have to make a flywheel of some sort (or maybe a spare prop shaft gear?) and color half of it black in order to have enough reflective surface to get an accurate measurement. Or, if the chassis could be held down well enough, perhaps remove 3 props and listen to the sound of the running prop and compare 100% to 150% to see if the pitch sound is higher.

zoandar: You could also measure the total current at the JST plug or use an optical tach to measure rpm with the props on.

I don't know if the 125% endpoint adjustment is ignored or not, though I agree with jasime2501 that the mQX definitely becomes quicker to react. Probably just because full travel is reached sooner and then maintained. As an example I find flipping performance of the mQX to be about the same with both EPAs, though it is a lot more skittish to fly on 125%.

Originally Posted by kodak_jack

72 Mhz on my first heli's by Esky was a curse! Nothing like the thing falling out of the sky and doing the chicken dance!! I have to agree with Larry that after the transmitter is turned on, you only have so much time to plug in the battery before the bind just doesn't happen. Like I've said, though, I've had to rebind my quad and transmitter 3 times in the short time I've owned it and the infrequent number of times I've flown it. This isn't with a cheapie stock game controller transmitter either.

One of the things mentioned on pages 22-23 of the DX6i manual is that either accidentally or intentionally powering it on the TX with the trainer switch engaged unbinds the TX. They said it was discovered that some folks using TX trays were having this happen by the switch bumping the tray when powering on. Apparently it is an instantaneous result. I know I have had to re-bind my HBFP and Blade 400 now and then. Not a lot though. But it seems pretty easy to accidentally unbind the TX. I wonder if that could also happen in conjunction with the presence of a lot of nearby metal when powering up the TX?

Originally Posted by jasmine2501

Ever play the "Chuck Yeager's Combat Simulator"? That was a fun game, and I'd love to see a modern version of it.....

Never flew the Combat Sim, but I had the original version of Chuck Yeager's Advanced Flight Trainer, and later V 2.0 - both MS-DOS versions. That was the most realistic flight-sim of the day. I had to upgrade to a whopping 256k of ram just to run it! I was (and still am) into MS Flight Sim. Started with subLogic's original FS1 for the TRS-80, and I've had every MS version from Flight Sim 1.0 though X.

Joel

The mQx manual says:

TIP: These are all possible with the RTF transmitter. When using a computer transmitter, however, increase the travel beyond 100% on aileron, elevator or rudder for maximum control authority

I would imagine that all this really does is affect how the 4n1 mixes channel inputs and doesn't actually increase the max rpm of any motor.

I haven't experienced the bind issue at all with my early run mQX unit. I have a dx7s. I've bound it three times in total but only because I bound it in advanced mode first then + mode to try it out and then back to X. I'm assuming all of the folks having bind issues are following the binding instructions from the mQX manual and not the radio manual? It does have a sort of nonstandard bind method.

Originally Posted by 4x4rc

When you do take it out I suggest you find a pasture or something with nice long grass. Take a box or a piece of cardboard or wood with you to take off from and land on. The grass will dampen any crash nicely regardless of the height. If you remember to cut power before reaching 0 altitude your mQX will very likely not incur any damage whatsoever.

My satellite anti-crash extreme kit.

enjoy,
Mtz