I'm not getting any reply on the OpenCockpit website (forum) so I post it here.I'm doing some tests here with the USB-Stepper card.Let me show you my SOIC code to start off with: //****************************** Var 0000, Value 0 // Initialization { V0001 = 255 // sets the servo position to step 255 of possible 1021} Var 0001, Link USB_SERVOS, Device 40, Output 1, PosL 1, PosC 512, PosR 1023, Type 1 //****************************** I save it as ssi file and push reload on the SOIC main window to set that value into the servo. To change I set the code to V0001 = 1 or V0001 = 1022 or anything else.When I set the servo value to 511 it should be centered, right ? Then I take the screw on the servo loose so that I can adjust the white plastic bar that is conected to the axis. I set the plastic bar straight in the center as a reference and screw it back firmly. Now the servo value is 511 so centered and the servo shows me a centered position. Now I set the servo value to 1022. The white bar goos around the axle counter clockwise .. +/- 100

Made a little website with some pics and a diagram to illustrate the problem and to allow to check if I soldered the kit correct or not.http://users.skynet.be/fb117960/iocard/servo.html

Did you connect the external +5V?//T

I have exact the same on my servos, some of them goes down to 95, most of them don't move below 190. I think the pulse from the servocards is the problem. None of my servos on any servocard has used whole range from 1 - 1024. The result is lower resolution as you only can use for example 190 - 1024. This is bad, but I have been lucky with my setup and manage to get what movement I need from the lower resolution.

Tigert > Yes I do power them 5V. So that isn't the problem.Johan > Thanks for posting that! Now I know I'm not the only one with this problem and now I can be more relaxed 'bout having soldered the cards as it should (not mixed up components).I have no idea which are the specifics of the IC on the card but if more people have this issue, perhaps it could be fixed with a new firmware ?I hear what you say 'bout being lucky with the setup and using the lower resolution as is .. I'm very happy too with a great deal of things.First there's the price of this product.Then there is the speed of shipment & deliveryThen there is the way OpenCockpit keeps you informed about the status of your shipmentThen finaly there is the print that does work (not 100% ok, but still 85%)And finaly there is the very handy SOIC software which takes little time to figure out.On the other hand there are a few points I'm not happy with.1) there should be a better step-by-step tutorial on how to solder up the kit2) the print should work 100%3) little more guidance about servo's and which ones are prefered to buy to go with this interface.

Try with different brands of servos too - at least on our Simkits gauges, HITEC's give a ~20 degrees better range than FUTABA. Since this is not a big issue on radio control model use, as one rarely uses the whole travel range, servos seem to differ a bit on the pulse response.//Tuomas

What's the price range on these HITEC's ?The one I got here is Protech B305. It cost me

Agree, there should be someway to tune the card to suit different servos. I'm too satisfied with opencockpits delivery and priceing but as you say, there is more to whish on the documentation and forum support. I belive that the spanish talking customers are more satisfied as that part of the forum is more frequently used and also have a lot more information in the documents.It should be possible to solve the pulse problem with a new firmware in the PIC.

Sounds like an issue to me. Since every single builder would require it's own personal firmware.An option would be for OpenCockpits to let us know which servo's work 100% with the hardware (and perhaps put them in the order page with the kits or finished products).Else they should try to make it possible to set the pulse rate via the software but I'm afraid that will require a new software & pcb layout .. or not ?PS: let me know where I can find that spanish forum !

Captains;I've been doing some math and measuring here.My servo turns 155

There is a way to do this without gears. I have modified my servos that need to have greater turn than original servos.I use a 340

That is well clever mate !Only I'm not too fond of messing with the internals of a servo. I've never opened one up. But I guess I could try.How do you determin which potentiometer you need ?

All the servos I have dissmantled uses a 5Kohm pot.

So the trick is to use the same ohm value but have one with more

>>PS: let me know where I can find that spanish forum !http://groups.yahoo.com/group/construccion_cabinas/SaludosPedro Bibiloni