Ditex servos

[Puttputt maru]

I just received some Ditex servos from Hacker Motor. This is related to Jeti because they have telemetry.
http://www.hacker-motor-shop.com/e-v...&c=8216&p=8216
http://www.ditex-servo.com
Some of the text on the last link is in English

I am not sure yet how useful the telemetry will be but I mainly got them because they are programmable.

The one special particularity about them, beside being expansive, is that they have no stop point. They will turn a full 360 and more. You program the zero point and you program the end point.

This means that you can have any servo arm at exactly 90 degree for your resting position and have any range of travel needed. No sub trim, no loss of travel range because of the sub trim.

Anyway just a new gizmo I will try.

[Dansy]

Let us know....how easy they are to program once your done, I'm thinking of trying them on my next plank project.

[aziz76]

I too was thinking of trying those. I would be anxious to hear how the telemetry works, EX or EX Bus? etc...

Do let us know once you have tried them out.

[Puttputt maru]

First report:

1) The software interface is really small on my Surface. I had to increase the screen display to 300% to make it visible to my poor eyes.(normal recommended by Window for the Surface is 200%). It will be nice when as promised in a futur update you can do the programming from the Jeti Tx.

2) I love it other than that.

The one great thing which was my main reason for trying these was the ability to set zero degree deflection exactly anywhere you want it to be AND retain full servo deflection both side without any subtrim.

You can also program the range as you like it, so if you need 60 degree just input 60 degrees if you need 200 degrees input it too.

As in a lot of other software when you make a change you have to save it but contrary to a lot of them as soon as you make a change the save button start to blink to remind you to save it or to warn you that you did make a change. A very nice touch.

Got to go look for a new house so more report will follow once I plug them into my Jeti Tx.

They have soft start

[Dansy]

I might be wrong but I believe on the Jeti when you use subtrim you just displace to either side? That's been my believe up to now??

[Puttputt maru]

Originally Posted by Dansy

I might be wrong but I believe on the Jeti when you use subtrim you just displace to either side? That's been my believe up to now??

No as with any Tx when you move subtrim to one side, that side will loose some travel compared to the other for the same stick movement.
Increasing the travel on that side will sort of compensate but still does not make each side feel the same.
Probably not very evident on a helicopter, thus not as important, but very much noticeable on a 3D airplane.

[cbdane]

Originally Posted by Puttputt maru

No as with any Tx when you move subtrim to one side, that side will loose some travel compared to the other for the same stick movement.

I don't think this is the case.

[flint723]

Physical trim buttons move center point but not end point.

Sub trim in tx should move the entire range including end points.

[Puttputt maru]

Well I don't know anymore. I could be wrong.

One thing for sure is that when I have set up 3D airplanes with my Jeti as with other Tx I still needed to adjust % deviation to get the same on both side 100% did not give me the same deflection when I had some sub trim.

[Dansy]

Originally Posted by Puttputt maru

Well I don't know anymore. I could be wrong.

One thing for sure is that when I have set up 3D airplanes with my Jeti as with other Tx I still needed to adjust % deviation to get the same on both side 100% did not give me the same deflection when I had some sub trim.

On 3D planes I would agree since we used the physical travel limit of the servos, but for Heli and normal airplane that shouldn't be the case.....either way I will try some of these this summer

[Puttputt maru]

Originally Posted by Dansy

On 3D planes I would agree since we used the physical travel limit of the servos, but for Heli and normal airplane that shouldn't be the case.....either way I will try some of these this summer

Yes I agree, as I had mentioned, that for helicopter we do not reach full travel anyway.

What I wonder is if you need less travel, if by limiting the range of the servo to for example 40 degrees since that would translate to 100% travel for the Tx, if it would give you a better resolution or not? May be resolution is not the right term.

An other nice point positive point for the servo, is that the tab to screw it in is all metal, so they made it thin which could be nice in some installation. My TDR would benefit from this.

[Dansy]

I'm not an expert on heli, just been back into them for a few months but the flybarless take all the direct feeling by inserting there own form of direct connection depending on who make the unit, back then I flew with mechanical gyro only.....piezo were just coming out when I decide to go F3A more seriously....

[Puttputt maru]

Ok well,it looks like I got had a bit I was expecting to have some telemetry reading one way with those servos to play with while waiting for the ability to program the servo later on from the Tx.

Kick note to Hacker USA and it turns out that nothing works as of yet. The telemetry reading from the servos is not possible yet and no date are set.

I don't blame anyone but myself for not inquiring more about it.

Still nice working servos and VERY quiet which I like.

[myxiplx]

Really? I thought they marketed these as being integrated with Jeti telemetry?

[Dansy]

I taught you knew about the telemetry, only the software is available....my understanding is that with the software you still see the amps from the servo connected so setting them up is possible?

I'm pretty sure that even if fun telemetry was available, I wouldn't use it after setup....to much would slow down refresh quite a bit....????

[Puttputt maru]

Originally Posted by Dansy

I taught you knew about the telemetry, only the software is available....my understanding is that with the software you still see the amps from the servo connected so setting them up is possible?

I'm pretty sure that even if fun telemetry was available, I wouldn't use it after setup....to much would slow down refresh quite a bit....????

Even amps from the servos is not possible as of yet.

Bummer but no biggy as you said not sure I would use it much after set up. Good thing I got the PC interface with my order.

You need to register to use the interface by the way. Just a simple process of giving them your email. Hopefully I will get updates with that in the futur.

The one thing that was confirmed is that a REX receiver will be needed and a tentative date is mid 2017 for the update.

[Puttputt maru]

My first report on set up the Ditex servos on my new built.

First, I love them

Extensions:
I usually do my own extensions the pic below shows a double connection I do for my aileron servos.
The white/red/black wires come from the outer servo which I had to extend the wire.
The white/purple/black are directly from my inner servo for which I had to modify the connection to use my double connect.
This was much easier to do than with my JR servos because the wire and strand are of a bigger gauge. Not quite as much as my extension, which is a 100 strand wire I get from taildraggerrc, but just as easy because it stays together and will not slip out of the crimp no matter how hard I pull on it.
Nice flexible twisted silicone wire wonderful for helicopter passing through anguilar spots but not fragile as some are.

SetUp:
Could not be simpler.
First just plug one servo and set with the computer where the zero will be no matter what type of arm you use the zero is zero once recorded. No subtrim at all. All done with 0.1 degree precision. I never had an arm so perpendicular to the servo. I cannot wait to set up a helicopter with them.
Second see how much travel you need for maximum deflection up and down taking care not to connect servo arm so you do not rip out the aileron. Input those values in the computer.
Repeat for the other servo. Done

I am still experimenting for max value if I should set it in the servo or the radio. You can also set fail safe position if you want within the servo.

Soft start of course adjustable at the speed you want.

I am just trying servo travel and current drain.

I am speechless. This is the most mechanically perfect airplane I have ever done or the Ditex servos are the best matched servos ever. Below are the reading I get throughout the range. Two different pictures with different aileron deflection, same results. I do get a transient 0.06 but even at full deflection they stay the same.

They seem to need some current at rest. With my JR at no deflection I would get a 0.00 reading, with the Ditex I still have a 0.05 reading at rest.

Did I mention slow start as slow as you want it. Great stuff

I just had to mention this too:

No buzzing from them

I really hated going to digital servos because of that buzzing.

Did I say I love them.

[Dansy]

I will have to get some to try before the summer.....thanks for the write up..

[prototype3a]

FYI...

https://www.rcgroups.com/forums/show...ostcount=27687

Looks like these servos really are next generation technology.

[Puttputt maru]

I cannot say enough about how impressed I am with these servos so far.

The one thing, pointed in the review link above, that really impresses me most is that the pulse range stays the same no matter how many degrees you need. This is not the case with any other servos.

This is great for all applications but I would think especially for helicopter where we never really use the full range the servo is capable of. Who needs 120 degrees total rotation on a swash or a tail.

So in a regular servo if you reduce the range to let say 60 degrees total you would cut the pulse in microseconds by half. Not so with the Ditex you maintain the full pulse range.