I have a black box DC to AC inverter with a 5 kΩ linear taper pot wired to it that acts as an LED light dimmer. I have no idea how the circuitry of the black box is composed - it is encased in a potting compound. The pot is wired up to the wiper and one end (like a rheostat) and the lights get brighter as the resistance increases.
I want to control the dimmer with an original dimmer switch. Unfortunately the original dimmer rheostat only has a 10Ω linear taper range – just a wiper across a wire coil and the resistance decreases as I turn the knob up – opposite of the 5 kΩ Pot.
I'm trying to find a simple circuit that will magnify and invert the 0-10 Ω range to a 0-5000Ω range to control the inverter. I'm not sure if an OpAmp can do the trick. I do know that the voltage running across the 5 kΩ pot is about 8 V perhaps I can use the OpAmp to mimic the expected voltage drop?
An Arduino and a programmable digital potentiometer seems overkill. Also, I haven't liked any of the options I could find to swap the wire coil with something of the right resistivity range.