Epa... Fix???

[jevyguy]

Originally Posted by YJ_Driver

Assuming you're running the servo off the 6.5V BEC, is that stretcher rated to run at 6.5V? That circuit might not work well or may have been damaged if it wasn't designed for that high a voltage.

I had the same situation using an old radio but with a HS7955, so my solution was to set the servo to normal resolution and tune the endpoints.

For you I think the only solution is a stretcher. Don't mess with the pots internal to the TX, they are NOT for EPA and you'll just mess something else up. I don't think there's anything simple you can do to the TX either. You could add two resistors from the steering's pot middle pin to the end pins, but no guarantees and your steering won't have a linear response.

Richard

I guess it is possible that I fried them, but there was also very little to no information packaged with them.

As of now I played with my programmer and got my steering to work almost perfect.

I still dont get 180* of travel with the rear servo that I would like. For some reason when I try to program my 5995 I end up with less travel then the factory settings, so all I can do with that servo is set the Dead Band Width. The servo is already programmed to 180* so I guess I wouldnt get any more with the programmer, I just think it is odd that I get less.

[clockworks]

Originally Posted by jevyguy

I guess it is possible that I fried them, but there was also very little to no information packaged with them.

As of now I played with my programmer and got my steering to work almost perfect.

I still dont get 180* of travel with the rear servo that I would like. For some reason when I try to program my 5995 I end up with less travel then the factory settings, so all I can do with that servo is set the Dead Band Width. The servo is already programmed to 180* so I guess I wouldnt get any more with the programmer, I just think it is odd that I get less.

The problem lies with the transmitter design. The transmitters that I've seen all have the same problem - it's not possible to move the stick/wheel/trigger far enough to get full movement of the servo arm.

Nearly all standard pots rotate through 270 degrees or so of rotation.
Put the pot in a Tx, and it simply can't rotate that far. 60 to 120 degrees seems to be normal. If you wire a standard pot (left loose, not fitted to the stick) in place of the Tx's pot, you'll get much more movement at the servo - up to double with one Tx that I've modified.

Computer Txs offer the option to overdrive the servo, up to 150% in some models. This goes some way to overcoming the problem.

[YJ_Driver]

Originally Posted by jevyguy

I guess it is possible that I fried them, but there was also very little to no information packaged with them.

As of now I played with my programmer and got my steering to work almost perfect.

I still dont get 180* of travel with the rear servo that I would like. For some reason when I try to program my 5995 I end up with less travel then the factory settings, so all I can do with that servo is set the Dead Band Width. The servo is already programmed to 180* so I guess I wouldnt get any more with the programmer, I just think it is odd that I get less.

I had trouble programming mine too with the HFP-10 and the HPP-21 where I lost almost all travel regardless what I tried to program; There seems to be a bug with the s/w either in the programmer or the servos. This problem only occurred when I programed the neutral position as per the instructions, even if I didn't want to change it. So now I only program the end points.

Besides, I don't even want a 'neutral' position anyways as my old radios don't have neutral at the same place.

Richard

[YJ_Driver]

Originally Posted by clockworks

The problem lies with the transmitter design. The transmitters that I've seen all have the same problem - it's not possible to move the stick/wheel/trigger far enough to get full movement of the servo arm.

Nearly all standard pots rotate through 270 degrees or so of rotation.
Put the pot in a Tx, and it simply can't rotate that far. 60 to 120 degrees seems to be normal. If you wire a standard pot (left loose, not fitted to the stick) in place of the Tx's pot, you'll get much more movement at the servo - up to double with one Tx that I've modified.

Computer Txs offer the option to overdrive the servo, up to 150% in some models. This goes some way to overcoming the problem.

The TX is designed to translate whatever travel your stick/wheel/trigger goes through to get 100% servo travel, regardless of whether the pot rotates 60, 120, or 270 degrees. Electronics can do wonderful things That's why they add EPA or Dual Rate that go to more than 100%, for those that want more than standard travel.

Richard

[oldhippie]

Originally Posted by YJ_Driver

The TX is designed to translate whatever travel your stick/wheel/trigger goes through to get 100% servo travel, regardless of whether the pot rotates 60, 120, or 270 degrees. Electronics can do wonderful things That's why they add EPA or Dual Rate that go to more than 100%, for those that want more than standard travel.

Richard

Most servos can travel past 180. Most radios are set up for about 90 degrees servo travel at 100%. I don't any radios that will push them to 180. That's what what the stretcher is for.

[clockworks]

Originally Posted by YJ_Driver

The TX is designed to translate whatever travel your stick/wheel/trigger goes through to get 100% servo travel, regardless of whether the pot rotates 60, 120, or 270 degrees. Electronics can do wonderful things That's why they add EPA or Dual Rate that go to more than 100%, for those that want more than standard travel.

Richard

I agree that's how it should work, but, in practice, it doesn't. The electronics compensate for the limited rotation of a trigger or wheel, compared to a stick, but they don't "compensate" up to full travel, just to match the less-limited movement of a stick Tx.Take the pot out of a Tx, or wire in an external pot, and you'll get a lot more travel.

I did this with my hybrid 6ch pistol Tx (DX6i electronics in a KO Mars case). A 5K pot, with full 270 degree travel, gave much more travel than the ch2 stick on the original DX6i.
Same on my current project (Turborix 6ch into cheap Chinese pistol case). A full rotation pot puts travel off the scale in the setup software.