gkpain

My Feedback: (1)

Heys folks,

I'm alittle confused, maybe yall can help me out.

Setup: Smart-Fly EQ10
Futaba 10CAG
Hitec HS-7955TG Programmable Digital Servos, with a hitec servo programmer
All of these make it possible to set endpoints and centerpoints(subtrim). Among other settings
Obviously you dont need all 3 to do this.
So, which one would be the proper one to use to adjust>???


You can change some of the settings with all 3,
but you can't change all the settings with all 3.
Such as dead bands or resolution, these must be set with a servo programmer

Thanks for your help
(GK) PAIN!

BuschBarber

My Feedback: (2)

Hitec Digital servos are unique in that they are one of only a few Digital servos that can be programmed. Various parameters such as Speed, Neutral, Deadband, Direction, and End Points can be modified. This is especially useful if you are trying to Match servos connected to the same Control Surface such as multiple servos on Rudder, Aileron, Elevator, or Flaps. If you have Dual Ailerons, for example, and they are connected to separate channels on the Rx, you can adjust Direction, End Points, and in some cases Speed via the Tx. Subtrim is primarily used to move the servo arm to 90deg after the servo direction has been set and the servo arm has been installed on the servo as close to 90deg as possible.

gkpain

My Feedback: (1)

Thanks for your reply BuschBarber,

I understand everything you said but,
The question is :

If you can program certain settings, such as endpoint and nuetral settings, with all 3 components,
which one do you program
the Servos, the EQ10, or the Radio>??

Thanks Again
(GK) PAIN!

BuschBarber

My Feedback: (2)

I have never used an EQ10 so I am not familiar with what it's features, however, I did check out the manual on the Troy Built site. There are functions of the Tx, Hitec Digital Servo Programmer, and EQ10 that are similar. You have to decide which you plan to use and for what purpose.

The Hitec Digital servos are programmed using the Hitec Digital Servo Programmer. There are 3 to choose from. If you have other manufacturer's servos or Analog Hitec servos, you will not be able to program them. The various parameters that are programmable on Hitec Digital Servos are outlined on the Hitec site. There are more parameters than can be set by the EQ10 or the Tx.

http://www.hitecrcd.com/products/ser...ers/index.html

The EQ10 has Buttons and Dials that let you adjust some of it's features. It's main purpose is Power Distribution, but I see it will also let you set servo End Points. It Isolates the power to the servos from the power to the Rx and regulates the voltage to each channel.

http://www.troybuiltmodels.com/items/QPEEQ10.html

Some people who use Hitec Digital Servos adjust the parameters of each servo before installing them in the aircraft, especially if the servos are connected to Y Harnesses. Unless you have each servo connected to a separate channel, you cannot adjust each servo individually with the transmitter.

For the most part, I use a mix of Hitec, JR, and Spektrum servos, so I use the transmitter to set up everything. There are those who are religious about programming their Hitec Digital Servos and the use the transmitter for all the rest of the setup.

A.T.

Always use the servo programmer rather than a Tx to adjust digital servos.
The main reason why programmable servo were introduced was to avoid the problems
caused by tx induced alterations to endponts etc.

Have just answered similar question on other forum as follows, includes links to full explanations:

"This also explains why setting the physical servo travel to 50% ends up not being the neutral position."
Not quite, Hitec use different spline patterns, many of which can not be set to so as to obtain arm at 90 degree without use of sub trim etc.
. Servo - Horn Centering & Spline Count. extract
"Unfortunately, simply turning a servo horn around does not work with all servo types, especially standard Hitec servos which have a 24 count spline -
Only those servos with odd numbered splines (say 25 spline) can be turned around to approximate center position.
Even then some sub trim may still be required.
Gone are the days when servos were hand assembled and hand set for centre point to be at 90 degrees.
There will always be variables with current production methods, no two pots absolutely identical. -(excludes digital servo.)
Servo - Horn arm Spline Count and Inter Brand Compatibility " - "Alan T.

. Digital Servo Programming FAQ - Center & End Point - Adjust to Match TX
"The programmer sets the end points at 900, 1500(center), 2100us when you use the EPA programming mode.
If your transmitter is not sending a wide enough pulse at it's end points, you will not see the same end point travel you set with the programmer.
If you increase the EPA settings in your transmitter for these channels you have the programmed servos on,
you should be very close to the end points you programmed. "
"The "100%" end points in your transmitter are not the same as the "100%" end points in your servos.
You may have noticed that the end points in your transmitter can be set to higher than 100% (different brands have different "more than 100%" settings.)
If you want the transmitter end points to match the servo end points, set the end points in your transmitter to their maximum.
If the transmitter is set to "100%", it is really using end points of greater than 900 and less than 2100.
I believe this came about because some early servos could not handle the full 900-2100 signal range."

. Digital Servo Programming FAQ - Center Point May Vary - Why & Correction

Above and much more information available under sub section:
"Radio Systems, Accessories, Alterations and FAQ" at
Alan's Hobby, Model & RC FAQ Web Links
e.g.:
. Transmitter - Pulse Width, extract:
. JR vs. Futaba pulse width
"FWIW MPX3010, 3030, 4000 Pulse width = 1.05 - 1.6 - 2.15 ms - Alan T. "

. Old Pulse width with new ESC extract
"NB: The old servo had a different pulse width to the modern, refer
Old Futaba Servos so ensure that the trim is reduced to minimum on your transmitter
and make sure prop is not attached to motor when setting up the ESC.-Alan T."

. added to follow up question:
These earlier posts may also assist:
EPA, ATV, Dual & Triple Rates, Expo Differences & Caution includes ESC / BEC Set Up.
Using the TX requires unequal travel set points - Using Programmer or TX.


Alan T.
Alan's Hobby, Model & RC FAQ Web Links

BarracudaHockey

My Feedback: (11)

Having worked with all 3

Reset the servos to default.

Use the EQ10 to set your servos so they don't bind if you're ganging surfaces, otherwise use your transmitter.

rmh

Yeh- screwing around with the servos is a path of last resort for me
The reason being replacing a servo or doing a field adjustment is going to require the programmer .
I have watched guys burn up servos trying to "fix" programming errors at the field
.
Being an old school guy - I always opt for first comparing servos to be ganged - then settings arms for identical positions then making sure all the geometry matches
Trying to correct for errors in geometry is futile
If the servos don't match - try others - most newer servos match quite well -
Any programming or subtrims should be very minor or you will likely end up with goofy , non linear servo action.

gkpain

My Feedback: (1)

WOW A.T. ,

Thats the kind of answer i was looking for!!! Thank you very much.

rmh,

I'm with you on ur ideas, but technology keeps changing and the old school stuff keeps disappearing.
I gotta keep up with the technology, besides some of this stuff is pretty cool and easy to use once you get some hands on.

Thanks again everyone.
(GK) PAIN!