I DO like the idea of programmable servos vise the matchbox, but I don't think varying TX pulses explains why every servo shouldn't be able to be mechanically set to a prescribed "zero" position. A TX "center" position with no sub trim offset should give a pulse width of 1.5 mSec going to the servo. I think that was Russian's point was this : theoretically, if you put two servos on a y-harness, they should both be able to be centered exactly the same mechanically (90 degrees to their arms, or whatever measure you like, but BOTH servos should position the same in this way without doing anything special -- correct me if I'm wrong, russian).

It seems to me, that the mechanical centering difference between servos issue is really the inability to mate the pots to a known output gear position. This is an issue on every servo, even analog servos. Once you put all the gears inside the package, and then locate the potentiometer to the output shaft which indicates actual spline position, I think it's tough to actually align the pot so it's dead nuts one spline to another when compared to a different servo. That's why it's just a lot easier to re-program the center position, which can be done much more precisely than gear or spline teeth can be positioned. Pots have manufacturing tolerances, and I just don't think it's possible to electronically trim them so they will match mechanically in this sort of system every time from one servo to the next.

As you mention the TX should transmit a control pulse at neutral of 1.5mS, seems they rarely do. It would be advantageous in some circumstance to offer all servos centered and end-point matched. BUT if you're taking full advantage of the programmer and servos theres no point as you'll match them to the specific TX and model application.

Why hasn't anyone stated the obvious. Don't purchase any "new" Hitec product until it has been fielded for some time. I now exclusively use the old tried and true 5945's. Why - because I've been bitten by the "new" Hitec bug a couple of times. Got hoodwinked into buying a couple of 6985's, just recently, before the word got out that these servos were no good for large scale, high torque applications. I really like the price point of Hitec servos, but this company leaves a lot to be desired in their fielding methodology and I think they loose business because of it.

Mglavin,

"If you learn how to properly utilize the programmer and understand its function completely you'll come to a better understanding of its distinct advantages over ancillary matching devices. "

The instructions that come with the programmer leave a lot
to be desired! I think that Hitec should include a more detail
and practical example to show how to use the programmer.

Stick2K

Mike,

Any response from Hitec on the 5955 problem?

Kato

I'm also waiting. Hope we get some response soon.

I'm building a QQ YAK 54 toc version and was using 5995 on the rudder but it is pretty scary that really no one has come up with a solution or a fix for these servo's,, so I will cancel my order also, until I here what is going on with these servo's. I really like hitec servo's and have bought atleast 20 in the past 2-1/2 years. I haven't had any trouble with the servo's ,but I can't afford to do thier testing on my plane.

Just forget about programmer and use them with match box if nessessary. That's all.
JR 8611 don't have programmable features and it's OK! Just use your Hitec 5955, because it is still 330 oz. and JR8611 just 260oz.
I'm going this way.

Well said.

I soon will be outfitting my Comp Arf 2.6 Extra with 5955s. If the specs are correct, they're too good NOT to use, even if I can't program them.

So, still no resolution on the BETA release of the 5955's?

The new version 1.04 is also loaded into the 5945s.

Thus far, the FIX is not available. Hitec is still working out the problem. No word on a timetable to date.

The servos are useable in any event as shipped, even with the deviation from programmed parameters bug once introduced to the programmer.

so these servos work fine right out of the box? the problems occur when trying to program them? i would like to use a couple of these myself.

mr. glavin, i've purchased several of these 5955 servos and have a question about programming them. as i understand it, when you set center and the endpoints on the programmer and then remove it, the servo deviates around 2 degrees. my question is does this happen each time and all in the same direction, and is it repeatable. if so, i can still match the servos using the programmer and use the transmitter to set center. if i remember correctly all of my 5945's did this and i just compensated and set each servo with no problem. thanks again. toby silhavy
www.silhavyaerosports.net

While each servo may differ slightly, the offset deviation is consistent of each servo. It simply becomes the programmed center and end-point parameter. There's no need to use the TX trims to set center or end-points, utilize the programmable features of the servos to match the TX. With an iteration method you can and should be doing this anyway.

Hey guys,

I would like to sell my hitec programmer. It does not work correctly with the new hitec 5955 servos, as the programmed positions deviate by about 2 degrees from where set. I don't know about the rest of you, but I'm not spending my money on defective products. Hitec has had more than enough time to tell us what is wrong and to tell us how they plan to fix the bug.
The first 50 cents takes the programmer. Contact me privately if you want the programmer.

Sent you an E-mail

THANKS MIKE! i didn't think it would be a problem. toby silhavy www.silhavyaerosports.com

Am I correct in thinking that it is still NOT safe to program the 5955 servos?

Guys...

I have 6 of these in a 40% bird that hasn't flown yet. Winter is still here in the NE. This is what I have learned:

Yes you still can program them.... to a point.

You can set:

Deadband, reverse them, EPA and center. I would avoid doing a reset at this time until Hitec gets their act together.

As far as the centers & EPA:

What you program into the servo initially is not what it is going to be once you hook it back up to the RX. The end points are WAY off. You just have to fiddle around and program more travel into the servo to get the desired amount of travel that you need. Same with the center.

After you get used to the 'hunt & peck' method, its a no brainer. Just an inconvenience.

Overall I would still recommend these servos. Still a great bang for the buck, even though their flawed. Once the bug is taken care of ( I would assume a flash of the software in the programmer) the 5995 will be in a league of its own. In price and performance.

Just my observations.....

Stan
WV

I am about to receive the 5955 and i must say i am feeling a bit ancious about using it. I do not intened to use the programer on it which is from one what i can gather the key problem but what concerns me is that I have had two reports back from a freind regarding the 5995. In one case the servo failed and remain at about 7% this was after only a handfull of flights, the plane was landed saifly and everything was ok. On the second instance the servo failed and locked at full delection and so the only way to get the thing on the ground without too much damage was a flat spin. Luckily the only damage was to the undercarriage but the consequences could have been far worse. In both cases the bottom of the servo had burnt out or melted i am not sure.

The concern is that i am getting conflicting veiws on wether or not the 5955 is the same as the 5995 with the exceotion of the 180 rotation and the mounting plate at the bottom. has anyone here experienced thsi problem with the 5955?

Mike, If I put one of the 5955 servo's on the rudder of my 28% airplane and don't do any programing. (just radio subtrim) will I run into any of the troubles that guys are talking about. such as the guy that says one locked up at full deflection and caused a crash.

John

I have one on order from Tower, they don't have them yet.

No problems utilizing the servo OUT OF BOX.

Mike...

I have a few 5995TG's (the robot servos) and as stated they come with 180 degrees of operation... Is it safe to program them to 90 degrees?

-David