how could i remove high fequency noise from from a low voltage signal from a sensor in an instumentation sysm?

Answer 1

Depends what you mean by high frequency, and it also depends upon the required response for the wanted signal.

I would personally run the signal through a ferrite choke, decouple it with a low value capacitor (2pF) then run it through a low pass CR network with a cut off frequency at least twice the maximum needed signal frequency.

Cheers.

Answer 2

For starters adjust your tau on your instrument to see if the S/N ratio improves.

If that fails to improve your reading or you lose too much signal look to see if the noise is a multiple of 60 Hz, if so you have background bleed and need to reinsulate.

If noise is not a multiple of 60Hz look to see if you have a magnetic source near the instrument and if so remove it. If you can not remove it, try rotating it 60 - 90 degrees.

If you can not move the magnetic source can you constructively interfere with the wave pattern i.e. dampen it (trough to peak)?

Answer 3

That is the reason we study about active filters,try design a first or secon order butterworth low pass filter with OPAMP, thi swould remove high frequency noise and because we are using Opamp the output of the filter can still be maintained at a detectable level.

Answer 4

Simple capacitor in-line with the receiving circuit. OR utilize a band-pass filter. OR place the equipment in a grounded copper, screen cage which is what we used at Motorola to work on sensitive equipment.

Answer 5

One or more RC sections could be used, each section will add 6db/decade of roll-off beyond the cut-off frequency. For a single section, the -3db cut-off frequency will be 1/(2piRC). For 2 identical sections, it will be the -6db (half-amplitude) point, etc.

You didn't mention any need for amplication, so I assume you don't require any?

Answer 6

if you run the signal through a Resistor Capacitor network that will filter out the noise.