Spektrum Dx6 Problem?

[Heliman450]

Hi all, this isn't really a new thread as I've raised stuff a while back concerning these transmitters. A farmer friend of mine has two Spektrum DX6 transmitters and I've returned to his Blade 450X (with AR7200BX gyro) to prepare it for him to use during his less hectic winter season.

Last time he used it the heli flipped over backwards as he tried to land from a low level hover narrowly missing him. I thought that he'd used the cyclic stick instead of the collective as that's exactly how it looked to me. Before I insisted on watching him use it he'd had a number of crashes and also had a big problem binding the helis with the transmitters. I got the binding problem fixed under warranty.

When I dusted the heli off to start the investigation, I was somewhat confused about why the swashplate was sitting at such an odd angle after the initialising completed. I went through the full setup process and carried out a quick test hover. All went well apart from a tendency to tip backwards during the hover.

I started the next phase of investigation by checking out the settings as recommended by Blade in the manual although they don't list the DX6, I worked on the assumption that the DX6i would be similar. My query......

There isn't a swash type "1-Servo 90 degrees" shown in the options of the DX6 or any other similar option to choose that would leave the gyro as the only source of defining the swash type. Could this be a source of conflict between the Tx. and the gyro resulting in the back-flip?

 

[Smoggie]

In the DX6 swash menu the setting for no CCPM mixing is called 'normal'.. see pic attached from page 36 of manual. This is the setting that must be used for the vast majority of FBL controllers (only exception i know of is the Align 3GX)

 

[Heliman450]

Cheers Steve, I'll look into it and let you know.

 

[Heliman450]

Hi Steve, I checked out the setting in the Tx. and it was set for 3 Servos 120 degrees. Switching it to the "Normal" results in a graphic showing the elevator servo at the rear, however, the servo is actually at the front not the back. My JRPropo DSX9 shows "1 Servo Normal" as the FBL setting with no graphic for the swashplate.

I'll go through the setup again tomorrow using a completely new model position and delete the old one. I'll let you know if it fixes the problem.

 

[Tony]

Steve is correct, you will select Normal in the menu. I know it shows the elevator in the rear, but no worries, you will actually set all of that up in the gyro and all will be well.

 

[Smoggie]

Yep, 'Normal' or '1 servo' mean the same thing. All it really means is that all CCPM mixing is disabled so each channel (aileron, elevator and collective) operate independently with no mixing between channels. The FBL unit does all the mixing. This would also be the setting you would use for 'old school' helis that had mechanical mixing.

 

[Heliman450]

Thanks for the feedback. My Jeti uses "Mechanical" for the same purpose so I'm aware of the need to make this setting.

To those of you with the greater depth of knowledge than myself, is the reason for the somewhat confusing difference in the Spektrum transmitter terminology something to do with that the DX6 comes from a generation before FBL systems?

Next time I get involved in investigating other people's problems I'll start with a clean sheet and do more research before making any attempt. Lesson learnt!

 

[Smoggie]

I'm not really sure why they call it 'normal' or '1 servo'. The DX6 that you are using in only a 2 or 3 year old design so it's very much in the FBL age. I think the terminology has probably been carried over from older generation transmitters. 'No CCPM mixing' would be the most straightforward name to give it, because that's exactly what it is.

 

[Heliman450]

I know from my own line of work that people tend to cling on to old terminology until a newcomer asks why. It's usually met with "errrrr, it's always been that way".

Being new to the hobby by comparison to most, I'd have expected it to be termed 'No eCCPM mixing' or much easier 'FBL Mode'

 

[Heliman450]

Hi all, sorry for the delay in coming back on this, I was a bit involved in my non-RC life. The heli flies after changing the Tx. to 'Normal'.

Thanks to Steve/Tony for the follow/up on my query.

 

[murankar]

My guess is that spectrum kept the naming scheme from the older generations. Keeps it consistent across all the systems.