Hi
thank you for the help the signal was a lot more steady, however im having a issue with wires. for example i use a short wire and the readings are 12.8 at 12v from my bench power supply however when i use a long wire more then a meter i get 12.1 which is a lot more closer to the value i require. i know its due to resistance in the wire and a fixed resistor would help, however where would i put it.
below are two images one which i have now and one where i believe i should put the fixed resistor.
which is correct
Current
Fixed
