My requirement is to transmit a 10 bit resolution, 2.6 kSample/s, 0-5V analogue signal from an absolute magnetic encoder 75 feet in the sky to a DAQ module on the ground. To keep linearity of the sensor data around the 0 and 5V boundaries the output load impedance should be greater than 4.7kohms and less than 100pF.

I expect the analogue output signal to vibrate a bit as its position minutely changes, but change overall very slowly since the shaft it is monitoring rotates at less than 1 RPM.

There are three complications to this.

- the signal has to pass through a slip ring
- the signal has to travel from a height of 75 meters to the ground - I have heard that long wires act as antennae for EMI and the height of the cable may affect this
- the wire carrying the signal will be no more than a foot away from wires carrying 3 phases of up to 40V of wild AC

My first question is: based on all of these sources of interference, does the signal  stand any chance of maintaining integrity when it reaches the DAQ module? I lack the experience with signals to be able to predict whether this is feasible or not.

If you think this is possible, do you have any recommendations for making it work? The only approach I know of is shielding the wire, and keeping it as far away from the power lines as possible.

Thanks for your help