MOTM

Nice basic concept Dave.  Here are a couple of other thoughts for a circuit
along those lines (stuff I know Dave already knows but didn't say).

Depending on the size of your joystick pots, you may want to put a resistor
on either side of the joystick to the PS rails.  The idea being to limit
the current in that pot.  Of course, if your pots are as big as 100K or
50K, they would not be needed.

The size of the 100K resistor can be adjusted to have a smaller (or larger)
voltage swing from the pot effect on output voltage.  In fact, part of that
resistance could be variable to give you a range control.  You could limit
your voltage range by the ratio of the fixed to variable.

While your at it, add another summing resistor to the input of the op amp
and put a pot for "DC offset"

And, before you finish, go ahead and add to more op amps so you have both
positive and negative swinging voltages at the output at the same time for
a given joystick movement.

Wait, I just described the Hendry DIY joystick circuit.  :

Larry

> From: Dave Bradley <daveb@...>
> To: motm@egroups.com
> See the attached image for a
> quick and easy schematic. The
> opamp type is not critical.