modulating and distributing tv over uhf and cat5

[Stephen <ukha@xxxxxxxxxxxxxxxxx>]

Hi,

If I have, say a dvd that outputs composite and a tv that accepts a
composite input, can I connect them direct rather than use a
modulator? It seems to me that modulating/demodulating is an extra
layer of processing that I could do without. If so, why do you
modulate?

I suppose the downside is that you have to run three cables because
you need R+L audio too?

Are there any cheap (but good !) stereo modulators out there?

With or without a modulator, what is the longest cable run you can
have for i. video and ii. L+R audio? Does modulation extend this
distance?

Why should kat5 be better than double screened coax?

My final question is, at the moment my freeview, vcr, and tv have the
aerial lead daisy-chained. Does this cause signal degradation? Would
it be better to use a loftbox or similar to give each unit its own
direct downlead?

Thanks.