1. How do I reduce a 10k rheostat's range (potentiometer connected as a rheostat) to get a rheostat of 500 ohms?
2. How do I reduce a 10K potentiometer range to a 5k, so that the two edge pins (not the wiper) present a 5k to a source?
I guess in both cases some combination of parallel adding resistances could be done?
It is not a fixed resistor divider, it is a potentiometer.
1. A voltage divider (volume control) that has to present an impedance of 5k to the source, but only a 10k pot is available to me. Current is not too important, as it will be low for audio.
2. A rheostat (used as a variable resistor only) that has to be adjusted from 0-500R, but only a 10k pot is available to me. Current is tiny as well.
Does the linearity degradation apply to the rheostat configuration also?
1. A voltage divider (volume control) that has to present an impedance of 5k to the source, but only a 10k pot is available to me. Current is not too important, as it will be low for audio.
1, As 10k pot still can be varied from 0 - 500ohm(This range is also coming under 0 - 10k). But you cant limit the pot value or you cant change in the circuit conditions. but it is linear if the pot is linear.
2,just connect a 530 ohm between variable and fixed point (in use), but this will not be a linear.
Code:
in 10 k position 10k || 530 = 500
in 5 k position 5k || 530 = 479
in 3k 450
in 2k 400
in 1k 330
in 500 250 ohms
in 0 0 ohms
You are just doubling the range from the 1st type. But the possibility of inclusion of more than 500ohm value can be avoided, so it can be used in real time circuits
If you are saying rheostat then also you have to consider the current rating required.