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Jeff wrote in news:tZOdnSDPoNLGL9vfRVn-
:

BTW, one of my "pet peeves" is using an inverter to power a small TV,
when there are plenty of TVs that run on DC more efficiently. You
should read the specs carefully, because many TVs have significant
loads, even when "turned off."

I think now is a good time to bring up the new TV in Lionheart Cap'n
Geoffrey handed me to hook up. It's a MUCH more efficient LCD model, a 19"
flat monster that's only 2" deep. We mounted it on one of those cast
aluminum swivel mounts with the two arms and locking joints around the
corner from her nav station at the bottom of the main hatch to the center
cockpit. Doing this allows us to swing the TV around so it can be used as
a big screen computer monitor for the Dell Latitude notebook that can also
be easily seen from the helm at sea so the watches can monitor their
progress on a bigger screen.

This TV/monitor was delivered with a 12V, 2A power supply dongle with a
cord. As the TV is to be mounted permanently to the boat, I simply cut the
DC cord off the dongle, noting its polarity that wasn't marked on the TV's
DC input jack. I pulled the cable through a hole into the nav station's
communications suite and connected it to one of the permanently-powered DC
fuses so it would always be running off the house DC power. Before
connecting it, I measured its 1.28A load, making it much more efficient
than the old CRT TVs that had such small screens and took up so much shelf
space.

When in port, we simply swivel the TV around to point at the cabin seating
and connect up City Marina's Comcast Cable to the custom cable I installed
into the boat's jammed-up wiring runs. "We can fit another cable in there,
right?".....(c; The cable jack for the dock link is next to the AC power
jacks and the coax is tywrapped to our main power cable.

Having seen it at E-docker's new home on J-dock, I got 4 more boats to
wire, now....for the WIVES!

Sorry I can't remember what brand the TV is but it's an odd brand. Just
read the voltage coming out of the power supply dongle on the LCD TV you're
considering and look for anything from 12-15VDC output from it. The DC
regulators are inside the TVs so it doesn't matter if it's off a few volts.
Runs great off batteries and is very little load to the monsters.

Having watched a surge suppressor explode from the AC line power at City
Marina since we moved, the TV's MUCH safer off hooked to the house
batteries than AC power!

Oh, one word on cable TV......ISOLATOR NEEDED!! Cable TV's shield wire is
hard connected to shore power ground! So, you hook up the TV to the house
batteries and you're connecting SHORE GROUND straight to the house battery
negative leads! Here we go with more galvanic isolator problems. Luckily,
we don't need to have any ground at all on the cable TV, so I've
constructed this really CHEAP galvanic isolator to keep the boat isolated
from cable TV's grounding system.....

coax center wire
--------||-----------
dock .01uF boat
cable 600V TV
--------||-----------
coax ground shield

The caps are disc ceramics and not critical, just as long as they pass
54Mhz up and block 60 Hz and DC, which .01uF does just fine. If your cap
is too small, channels 2-6 may come in snowy as dock signals usually suck.

Voila - Cable TV galvanic isolator. Mine is in a plastic pill bottle with
two F connectors, one on each end, behind the comm station panel....NOT
grounded!