Riverdancer

My Feedback: (5)

Good Day Mike,

I am finally into the digital world, they are great servos however I do have a problem with the programer? I am not sure if I am on glue or what here but when I try to adjust the centering and end points I have troubles. The way I read the insturctions is you set the certer and then adjust the throws at either end.. The centering works fine but when I set the end points for a given angle and plug the servo into the reciever I only get about 75% of the throw I dialed in. Yet when I set the fail safe location it goes to the setting perfectly.

Thanks in advance for your help, by the way the dual rates and end points in my transmitter are set to 100% so its not a rate issue. If I reset the servo I get full throw out of it. (I think about 65 degrees +/- comes to mind)

Take Care for now,
Riverdancer

MikeMayberry

My Feedback: (1)

It's hard to trouble shoot things like this over the forums. I would suggest you contact our service department @ (858)748-6948

They will help you figure it out.

Mike.

hilleyja

My Feedback: (3)

Mike,

I've noticed this myself. I appears the ratio between the programmer and the transmitter is not 100%. It is also alluded to by the gentleman who put together the programming videos. I've gotten into the habit of initializing the setting of the endpoints with the programmer and then check them with the transmitter. Using the value from the transmitter setting, I then adjust the programmer plus or minus until I arrive at the point where they are 100% with the transmitter.

BTW, now that I think of it, my primary transmitter is the Futaba 9C. I will check this out with my Eclipse 7. I do know the Futaba's centering is ~1518 and the Eclipse's is ~1500, the endpoints are also probably different.

mglavin

My Feedback: (31)

There is no ratio between TX and RX.... The 225-0-225 scale of the programmer is a scale in of itself. The TX transmits 900-1500-2100usec (end-point/center/end-point).The servos react to the signal transmitted and subsequently decoded by the RX. The servos once programed to a specific center and end-point require a signal with a like value pulse width to duplicate the programmed parameters.

If you program the servo to move to a given end-point, this new programmed end-point is at the extreme end of the pulse width range (900 or 2100usec) and reacts to same. You can not realize this pulse width at 100% ATV, you need to max out your TX to realize this signal value. 100% ATV likely transmits a signal value around 200-300usec below the required value to drive the servo to end-point.

Transmitters don't usually deliver a neutral/center pulse width signal value of the desired 1500usec, design parameters, acceptable mechanical, component and bench tolerances typically provide a wide cross section of values, 1518usec is not unusual or anywhere in between for that matter. Of course 1500usec is best as this allows for linear values either side of neutral.

ScottK

My Feedback: (9)

1) When you reset a servo, what equivalent value on the programmer are the endpoints set to? 225? Something less?

2) I'd love to max the ATV & Rates for Tx/Rx resolution and not overdrive the servo. Any idea what a ballpark endpoint number on the programmer would be to run ATV at 125% and high rate at 140%?

(I guess I could just experiment with a degree wheel, but if someone knows this already...)

Ozmodeller

Like Riverdancer I too had many problems setting my digital servos (5645's and 5945's) to do what I wanted, I now have a procedure that takes approximately 2 minutes per servo as follows:

Manufacture a degree card (I used some stiff cardboard with a cutout for the servo) with a centre line and maximum throw ( 60 degrees) this should be inline with the servo spline,

Fit the output arm you intend to use,

Reset the servo,

Set the deadband and direction,

Set the centre and endpoints required (I always set to 60 degrees), and

Fit to model and play with Tx to achieve the desired throws.

Whilst this process may not work with every application, it does work for me and I am now a happy Hitec digital servo user.

Regards

Peter

mglavin

My Feedback: (31)

I'll have to reset a servo and find out where it travels too. If memory servos me its approximately 60 degrees travel in either direction. Where it falls into the scheme of thing with the programmer's epa scale is unknown to me. Not sure why you need this information. Its not relevant when programming or setting up servos to the best of my knowledge.

You cannot overdrive these servos. There was a time early on in their release when this may have been an issue TX dependent. The accepted parameters are now well outside the range of causing a problem to date. You can max the servo out to 225-225 with the programmer at extremes if it serves your needs. However the travel arc will likely be 180 degrees plus, which is unusable for our needs. Simply program the servo for the desired travel of the specific surface and then turn up the percentages to the maximum allowable , less 5-10%. Check for binding, if you have binding reprogram the servo with say 10 points less (if the servo was programmed at 200, try 190 and check again).

I have yet to go here, I have a degree and a jig for such setup but find programming the servo in the model is more benefical.

mglavin

My Feedback: (31)

Peter

Your method is more than adequate for most purposes. However there are some short comings and limitations with this procedure. In other words your not taking full advantage of the programmable parameters of the Hitec servo.

hilleyja

My Feedback: (3)

Following the procedures detailed by Joe Hunt on his 3 videos:

NOTE: These programming steps only concern themselves with center and endpoints of the servo. Deadband and servo speed default to reset positions and are generally assumed to be at their smallest possible deadband and fastest possible speed) and direction is properly set (use programmer's cw/ccw function to set). Also, I am using a Futaba 9C TX as an example.

1) Initialize your TX controls, set your subtrim to 0 and (personal choice here) set your left and right endpoints to 125 (Futaba -- not quite max deflection).

2) With the servo installed in the airplane and the servo arm removed connect the servo to the programmer and run the reset function.

3) Go to the EPAneuFS (EPA, Neutral and Failsafe) function of the programmer. Allow the function to find center and then initially move it to 0.

3) Connect the servo arm to the servo. Adjust the programmer knob until your servo arm is exactly 90 degrees to the case (you can use your prefabricated angle cards to help here) and set your center. Also at this time initially set your left and right endpoints to center + and - 150. (E.G., if center is -4 then left is -154 and right is +146).

4) Return you servo to center and connect your control to the surface horn. Adjust your clevis until your control surface is NEUTRAL.

5) Connect your servo to your RX and check neutral with your TX. Take note of how far off true neutral is.

6) Reconnect your servo to the programmer and adjust and set your center taking results of step 5 into consideration. Take note of the center number.

7) Reconnect your servo to your RX and check neutral again. Rotate through steps 5-7 until your programmer's center value gives your a corresponding neutral deflection with your TX. Take note of the final center value.

8) Still connected to the TX, deflect your control to full left. Measure deflection and take note of the difference between what it is now and what you want it to be. Do the same with full right.

9) Reconnect your servo to the programmer. Set the center value to the final value derived in step 7 and set the programmer's center. Adjust your programmer knob counterclockwise to the value derived in step 3 and then further adjust it to an approximate value in direct ratio of what you noted in step 8. (e.g., if deflection in step 8 was 1/2" too short then add about 10 to the servo value and reset left endpoint.) DO the same for clockwise and right end point.

10) Reconnect the servo to the RX and recheck the surface deflection with your TX. Repeat steps 8-10, refining your adjustments with each loop, until your programmed deflections matches your TX deflections. You are now done because you can assume the servos are linear across their throws.

IT IS THAT SIMPLE!!!

Ozmodeller

Michael

I admit that my procedure may be a little agricultural but being somewhat technically challenged and not having access to someone with your experience it does work. However, I am always seeking further ways of improving myself and the performance of my equipment/models, I would appreciate if you could advise what more I can do to take full advantage of Hitec digital servos.

Regards

Peter