28 Oct
2012
28 Oct
'12
3:46 p.m.
On Sun, 28 Oct 2012, Chris Green wrote:
Yes, I'm conscious of the grounding problem. While the boat wiring (the batteries are on a boat) is quite well behaved in having a single earth point to the hull etc. the length of the wires to the voltages being measured are such that there may be problems.
If the "grounding problem" you're worried about is magnetic pickup, then one traditional solution is:
- start with a wire twice as long as you need - bend it round a fixed support at its half-way point - sticky-tape both ends of the wire to the chuck of a power drill - turn the power drill on for a few seconds - cut the wire at the bend.
Hey presto, you've got signal and ground wires in a twisted pair.
--
HTH,
Dan