amplifier/splitter/isolator suggestions needed

[rnewman]

I want to expand my tuners.
Analog tuners for cable
digital tuners for cable
digital tuners for ota
BUT
cable signal I need to amplify/split/isolate
any BEST cable amplifier recommendations?
any way of isolating each output (ie:buffer) from splitter?
dual tuner cards pickup some beat harmonics that show up as herringbone
but some tuners can also pickup harmonics/herringbone from cross coupling
through the same splitter from another tuner.
That is why the need for isolate/buffer.

I also would like to combine signals from four HD antenna (north/south/east/west) to a common cable.
(need to isolate before combining?)

Most cheap amplifiers add too much noise to the signal.
Need really good recommendations.
Maybe several small gain amps to isolate.

Any suggestions appreciated!
Thanks,
Ray

[Opus4]

Here's my topic from when I asked about amps. Electroline amps are supposed to be pretty good.

You might want to describe your layout because that could affect what someone recommends.

- Andy