Bruce,

Thanks for the response. I'll have to study what you offered and digest
it for awhile.

The short description of what I'm up against is that I an installing new
electronics on a 1970 Chris Craft that I've spent the last four years
restoring. The boat is in Tampa, Florida and as soon as it hits the
water I will need to bring it home to the Caribbean where I live. I
will not have more than a few days time in Tampa where I have some
resources available before I take off. The shake down will be as I
cross the state to the east coast.

At this time the set up is Autopilot, VHF, Twinscope, GPS/Chartplotter,
and Radar at the lower helm. To the side, away from these will be the
SSB which I have not purchased yet. The VHF will also be operated from
the upper helm by way of a remote extension microphone. Both VHF and
SSB antennas will be mounted on opposite sides of the flybridge. This
is a separation of about eight feet. The radar antenna will be on a
mast above the upper helm and to the rear of the radio antennas by about
6 feet. I have just about convinced myself to install a second station
setup on the flybridge. If I use a second radar the antenna will have
to mount above the other one on the mast. I do not expect to use both
radars at the same time since I can't be at two places at once. And it
would require really extending the radar mast to separate them.

You said that you must eliminate noise at the source. My idea or
question was that if I put capacitors on each power feed to each
instrument, would this eliminate it as a potential source of trouble?

What do you consider to be a "good" alternator filter?

I have head differing opinions on positioning of the antenna tuner.
There is enclosed space under the bridge console and since this is near
where the antenna would mount I was thinking to mount it here. The
transceiver would be located on a shelf in the cabin within reach of the
lower helm. The boat has a built in counterpoise formed into the
fiberglass hull below the engines.

I'll have to figure out what size capacitors to use across the various
motors.

Thanks again for the response.

Earl