Question 2. When and where should I use twisted pairs and why not just
twist everything, everywhere?

My hi-tech Xantrex / Statpower battery chargers produce terrible amounts on
noise on my shortwave radios. I've been told that twisted pairs from the
outputs to the batteries may reduce this. Not got up the engergy to do the
re-wiring yet. By the way, this noise is radiated rather than transmitted
down the wire with the DC.

Using twisted pairs for wire carrying clean DC, e.g. from batteries only, is
just extra work for no benefit. I suppose some electronics might feed noise
back up the DC line but I would think this unlikely in newer
equipment.......but maybe not battery chargers?

"Earl Haase" wrote in message
...
I am about to start a major rewire on the boat. Which brings up some
ideas and questions.

Idea/question 1. I have seen those expensive power filters for boating
electronics. Why can't I just build a dedicated power buss and drop
some capacitors across the power feeds to each instrument? As in going
back to when we had to build our own power supplies for computer floppy
drives.

The electronics I will be trying to protect are ...
VHF
GPS/Chartplotter combo
Scanning sonar (Interphase)
Radar
SSB
Autopilot

And I may put a second radar and/or scanning sonar at the upper helm.

Question 2. When and where should I use twisted pairs and why not just
twist everything, everywhere?

Earl Haase