Quote:
Originally Posted by ProjectSHO89:
Keep in mind that, in almost all cases, you cannot combine your OTA signal with the
cable internet service on the same cable at the same time....
Quote:
Originally Posted by
domino92024 
Ya can if you first filter out signals >800MHz and <40MHz.
It is important to understand WHY you can't "share" the same coax for OTA and Cable.
Cable occupies nearly every frequency. Channels below 50 MHz are occupied by cable
modems and cable boxes/DVRs uplinking control/data signals to the local hub.
Channels from about 50 MHz to the cable system max frequency are fully populated
with TV and cable modem downlink data signals:
http://en.wikipedia.org/wiki/North_A...on_frequencies
So when you try to combine your very weak OTA signals onto the Cable Coax, they are
hopelessly buried below the strong cable signal levels. And even if your Cable system
had an unoccupied channel, the very strong intermodulation noise bleeding into that
channel position would still be much stronger than the weak OTA signal.
If you are a "Bare Bones", i.e. "Basic Cable" subscriber, the Cable system's
"Expanded Basic" filter probably only attenuates from about Ch20 to Ch70.
But probably NOT ENOUGH to suppress cable channel leakage on top of your
weak OTA signals...and those pesky out-of-band intermodulation noise products
will still be a problem if they don't also filter out the Digital Channel Tier, which
they probably DID NOT DO if you are an INTERNET only subscriber.
There are also
LEGAL and
Safety-Of-Flight problems if the strong cable signals were
to leak out via your OTA Antenna. And BTW, 20-30 dB port-to-port isolation in the
combiner is nowhere near enough to drop the cable signal leakage to acceptable levels.
And finally, if you are injecting your OWN RF Video signal onto a Cable Coax,
a Single Channel Injection Filter AND an isolation amplifier are essential to
prevent leakage of those signals back into your neighbor's cable systems.....
