Hi, I'm looking for opinions on the following, thanks.

We're making the move to OTA DTV for our whole house, having weaned
off cable. I have a decent antenna mounted on our roof with a
rotator. There's a Channel Master amp mounted at the antenna also. I
haven't measured distances so I can't quote specific cable lengths, so
I'll just state that our house is a garden-variety, 2-story Colonial.
I've been using this antenna w/ our main TV and the results have been
very good. My current assignment is to now distribute this signal to
other outlets in the house.

I'm using RG-6 for everything.

The antenna cable runs out of the amp on the mast down into the wall
behind our plasma. There, I'm splitting it: one half to the plasma,
the other continuing down into the basement, then to my electrical
panel at the opposite corner of the house.

When the house was built all the bedrooms were wired for cable tv.
All of these cables feed in-wall "F" outlets and meet at the panel in
the basement. Currently there are 6 of them.

My first assumption was that, since I am splitting behind the plasma,
then running an approx -3dB signal down to the panel, I'd be better
off with a distribution amplifier there (rather than a splitter), so I
picked up an 8-output unit (Channel Master 3045).

The dealer stated that I MUST terminate any unused outputs of the
dist. amp., or I would "lose power". I'm not sure I follow this -
wouldn't unterminated outputs cause ringing, rather than a loss of
output? Or would one cause the other?

If I used a passive splitter at the panel instead, would its unused
outputs also need to be terminated?

I did note that the 8-way passive splitter previously installed by our
cable company had several unused outlets, none of which they bothered
to terminate. I wonder if they're ignorant, lazy, cheap, or this
termination business is a myth.

Thanks for any advice/insight...