Jumpy, jerky yoke possessed by Satan

My homebuilt yoke project is not going very well. It uses 2 Radioshack 100k rotary pots with a Bodnar card. I have tried every possible setting calibrating it with FSUIPC (for FSX). The virtual yoke moves unpredictably, either too much, too little, not at all or with the real yoke not being moved at all. I have checked my connections and changed out the pots with the same unpredictable behavior. It sometimes seems that 1 axis will work correctly and the other erratically, but its hard to tell. It seems to vary. The Y axis seems to be a little more predictable. I think I am missing something fundamental about building controls, but I'm not sure what. Any thoughts? I am considering giving up on doing this portion of the sim myself, but it seems like it should be easier than this.

Thanks for the help.

First thing to check: did you get linear pots or audio taper pots?

They are linear taper

I would suggest using 10Kohm LINEAR pots, not logarithmic!

Cheers Westozy

Thanks for the help. The problem turned out to be mechanical. My yoke uses a little gearbox to drive the pot. When I put thension on the yoke shaft with a spring, it causes the gears to bind and slip on their shafts. When I take off hte spring and align everything mechanically, it works great. So I will have to go back and build a more robust gearbox that can cope with the tension of a spring.

Westozy, how does a 10k pot differ from a 100k pot in how it performs in a yoke setup?

Thanks for the help. Yoke building is harder than I thought.

You should also wire them as a voltage divider, not a variable resistor.

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Originally Posted by orwell84

Thanks for the help. The problem turned out to be mechanical. My yoke uses a little gearbox to drive the pot. When I put thension on the yoke shaft with a spring, it causes the gears to bind and slip on their shafts. When I take off hte spring and align everything mechanically, it works great. So I will have to go back and build a more robust gearbox that can cope with the tension of a spring.

Westozy, how does a 10k pot differ from a 100k pot in how it performs in a yoke setup?

Thanks for the help. Yoke building is harder than I thought.

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There is not really a great deal of difference when using a 10k or a 100k pot, the interface cards measure the change of position rather than the actual resistance. I think most card manufacturers recommend 10k pots and I have stuck with them since when I first had a SimBoard set up. I sell rudder sets fitted with a BU0836 card and 10k pots, they work well and are easy to calibrate.

Cheers Gwyn

Hi !

as far as I know fsx will work best with either 5 or 10 k pots, max is 20 k if I remember correctly

linear!