Searching for servos.

Hi.
I'm looking for propotional servos for a small robotic projoct, where I need small servos that can operate minumum 270 degress, but have not
been able to find any.
Most servos I have found either - turns approx 170 degress, and that's not enough for my needs, - or is continuously turning, witch is to no use as I need to be able to move to a specific location.
What I need is a largely a device like this:     http://dx.com/p/mg995-tower-pro-servo-gear-for-r-c-car-plane-helicopter-148051?item  except that it a rotation-angle of at least 270 degrees. 360 or more would be even better ;-)
Do you have an idea on where I can get such servos?
I would be happy for any hints on where to find such servos.
/Henning
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On 18/09/2012 00:36, Henning Wangerin wrote:

You could obviously install an additional 2:1 gear train with that servo therefore giving you 360 degrees but at half torque.
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Richard

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You can use gearing to increase the angle turned or even have the driving motor turn a counted number of whole turns.
Michael Bell
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IIRC you could modify the feedback pot drivetrain to not be a 1:1 gearing. You'd have to do a bit of re engineering, but mounting the feedback pot off to the side, instead of under the output shaft, and using a couple of appropriate gears would mean servo controlled feedback is still operable, but the resolution is of course reduced
Dave
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Not sure whether it is possible with current crop of radio control servos but it used to be possible to change the throw by adding a couple of small resistors to the end connections on the feedback potentiometer.
Henry

http://dx.com/p/mg995-tower-pro-servo-gear-for-r-c-car-plane-helicopter-148051?item 
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