Ground Loops, Pick-up and

It is possible for a small variable current to flow around the loop. That variable current will give rise to a variable voltage which will cause a distortion of the signal voltage. 

The symptoms can be degraded resolution and a very noticeable sinusoidal waveform at mains-supply frequency (50 or 60 Hz) on the signal - which, although often accompanying a ground loop, should really be regarded as pick-up from the AC power hne. 

Ground loops are most often found when different parts of a system are grounded at different points on the supply hus. They will be exacerbated by faulty cables, poorly attached coaxial plugs and by intermitted discontinuities in the grounding of signals caused by loose connectors. In general, the user should try for one effective common ground for all parts of the system in practice, a considerable amount of trial and error could be required. 

The following hints and tips may be useful. Some of these are sometimes incompatible  

When seeking to eliminate EMI as a source of resolution degradation you might consider the following  

---