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Unread 18-01-2005, 17:02
Dave Flowerday Dave Flowerday is offline
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VRC #0111 (Wildstang)
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Re: Are 100k Ohm pots necessary?

Just wanted to point out that
Quote:
Originally Posted by IFI RC Reference Guide; page 8
Always use 250 – 100KΩ potentiometers.
only applies to the Robot Controller, not to the potentiometers used on the Operator Interface (unless IFI changed the circuitry in the OI, but I doubt they have). The OI has a different circuit than the one Joe posted such that if you use anything but a 100K pot you will not get the full 0-5V range.

For those who are interested, this is done so that if there is no joystick plugged in, the analog inputs get pulled down to 0V and the OI can detect this and in turn send 127 to the robot (instead of 0). It's a safety feature so that if your joysticks get unplugged your robot doesn't start driving backwards at full speed.