Split/Combine

Pollux

Hi,

I was wondering if it is possible to split and then combine the signals coming form the LNB and a normal aerial. The following diagram will illustrate what I am asking:

[FONT="Courier New"]
    LNB          Aerial
      |            |
      |            |
      |-----|------|
            |
            |
      |-----|------|
      |            |
      |            |
   Decoder         TV
[/FONT]

The reason I am asking is because my house has been wired to bring a cable/aerial connection from the outside but there is only one cable. I think both signals are at different frequencies so I am not sure if normal splitters/combiners will work. Also I am not sure about the signals power...

Can any body tell me if this is possible and if so recommend the splitter/combiner to use?

Thanks in advance.

watty

It is possible but unreliable.
Also existing cables are rarely the quality needed for Satellite LNB.

Satellite LNB 750MHz .. 2100MHz
Cable TV / MMDS LNB 50MHz .. 420MHz
Band III TV 170MHz .. 300MHz
UHF TV 470MHz .. 860MHz
FM Radio (Band II) 87MHz .. 108MHz

The satellite LNB cable also carries 22kHz tone and 14V / 18V power
The MMDS cable carries also 12V power for its simple LNB
Cable TV cable often has high levels of AC Mains voltages which can interfer with or damage non-TV tuners or cause a loud hum. TV tuners in TV and VHS have about 750V isolation. "LNB" tuner in Satellite receiver has only about 50V isolation or less.

Satellite LNB needs double screened quality coax to :
Avoid reducing the > 900MHz signals
Stop interference "freezing" picture (e.g. Mobile phones)
Stop the stroing LNB signals that cover all of 750MHz to 2100 MHz simultanously getting out (e.g. interference with Mobile phones, TG4 on ch68 etc)

watty

You do need special Combiner/Splitter. But fit a separate cable.

Anyway they shouldn't be comming from same place. My sat cables all come into house about 6" (150cm) above ground.