I need to control something by hand that should look pretty (like a pot with a knob).
I need to control create a 1V-5V signal which comes from a 5 V or 48 V source (only need 1 and i figure 5 V is easier to use)
I was wondering if there was anything simpler than using a pot with a buffer after it?
I have done this before but there is tolerances on the resistances etc.
A pot is pretty simple. There are cooler things ( like a rotary encoder with flywheel ) but not simpler ( unless a fixed voltage divider or a knob connected to nothing ).
If you go with that circuit, be careful to pick a rail-to-rail op-amp. You also won't be able to go fully to ground with that circuit either. You can remove the 500 ohm resistor, doesn't look necessary.