Hi Mike,

Is there a trick in trying to get two servoes to match. I can't seem to get them to match perfectly. I have 2 5945s for the elevators but one always deflects more than the other. The linkage geometry is identical. But this also happens when they are not connected to anything and laying side by side. I am using two separate channels for the servoes on a Futaba PCM rx.

Any help will be appreciated.

Azhar

PS: Do you respond to your PMs?

According to Hitec's FAQ you have the following capabilities for programming the digital servos:

End point, center point, servo transit speed, and dead band width.

If you have each of the above matched and you still have deflection differences they must be related to control binding.

Hi Jim,

I do not think that i have any control-binding issue but would give a look. I have got to play with the programmer some more to get a better feel of it. Hopefully Mike can give us some tips here. Otherwise I must be one dumb programmer.

Azhar

The best thing to do is set up a jig with a long arm and match the travels.

Mike.

Mike,

I was just thinking about that myself. I just thought that with everyone mentioning how trivial it was that I must have missed something. I'll try that.

Is it normal though for the numbers to be different for individual servoes to have an identical match?

Azhar

Absolutely. The numbers always match on every servo when they come out of the box. Matching them means you match the physical travels and center points, the numbers mean nothing at this point, except for reference.

Mike.

Thanks Mike

Azhar

I don't remember if it was here, or on one of the other boards, but is it possible to program 5945's while installed in a plane?
There was some discussion about the extensions giving a false position or something? Thanks_bob

azhar

Which Futaba TX do you have? Some of the earlier TX's had an issue with frame rates (software) between channels with mixes.

Are you using desperate channels to with a mix to drive the elevators, wyes, HD extensions?

Did you try and use ATV or end-point travel adjustment to match deflection?

Michael,

I am using the Futaba synthesized rx. The two servoes are on separate channel. They are not y'ed. The extensins are HD. No, I did not use ATV as One servo is slaved to the other. May be I will give the ATV to adjust the end point. Thanks



Azhar

If the servos are pretty close matched for (even if they are not its doable, not the best method though) end point adjustment and centers, there is nothing wrong with using the end point or ATV adjustments on the primary and the slaved channel. I typically do this.

It is not uncommon to see a slight difference in speed or activation of the surfaces with any computer radio. Some early TX's it was quite obvious, other remedies were required to solve the problem.

Michael,

I will give the ATV a shot tonight and see how it goes. Thanks for the help.

Azhar