CATV and OTA Antenna combiner/splitter
 

I'd like to combine the digital cable going to my Comcast digital CATV
box with the downlead from an OTA antenna. I want to combine the two
into a single coax, then split it again at the TV. The OTA split at
the TV will go to the RF input on my new HDTV with integrated HDTV
tuner to pickup the OTA digital signals, and the CATV signal will go to
the cable box. The cable box connect to the TV/monitor via HDMI.

That way, I can watch all the HD content from my cable provider via the
HDMI input, and also get the OTA digital signals the cable company
doesn't provide by simply changing the source I'm watching from on the
TV.

I know for satellite dishes this can easily be accomplished with a
diplexer on each end. I previously had DirecTV and this worked great.
But is there a similar combiner/splitter available for CATV?

Any help greatly appreciated.

CATV and OTA Antenna combiner/splitter
 

Too much cross talk between channels, co-channel and adjacent channel
interference. Normally the cable suppliers will move the channel centre
frequencies a bit to allow more channels to be put into the same space.
injecting other information into that stream will only cause un-wanted
interference.
wrote in message
ups.com...
I'd like to combine the digital cable going to my Comcast digital CATV
box with the downlead from an OTA antenna. I want to combine the two
into a single coax, then split it again at the TV. The OTA split at
the TV will go to the RF input on my new HDTV with integrated HDTV
tuner to pickup the OTA digital signals, and the CATV signal will go to
the cable box. The cable box connect to the TV/monitor via HDMI.

That way, I can watch all the HD content from my cable provider via the
HDMI input, and also get the OTA digital signals the cable company
doesn't provide by simply changing the source I'm watching from on the
TV.

I know for satellite dishes this can easily be accomplished with a
diplexer on each end. I previously had DirecTV and this worked great.
But is there a similar combiner/splitter available for CATV?

Any help greatly appreciated.

CATV and OTA Antenna combiner/splitter
 

CATV and OTA Antenna combiner/splitter
 

Unfortunately such a simple device will not work correctly for combining
OTA and cable signals onto a single cable since the actual frequencies
of some of the channels will doubtless overlap. The only way it could
work is if the frequencies of the few OTA channels that your antenna can
pickup do not overlap with the used channels in the CATV system. You can
find frequency charts around that list the frequency ranges for each
channel to evaluate that possibility. Any overlapping channels will
suffer from co-channel interference. Depending on the relative strength
of the overlapping channels, you may receive the digital signal and lose
the analog one, or vice versa.

To solve this problem would require some kind of frequency shifting
(stacking/destacking) equipment that could band-shift the CATV band
(50-900 MHz) above the 900 MHz ceiling where you combine them on the
cable. At the receiver end, you would have the corresponding destacker
unit to provide two output signals, OTA and CATV.

Currently I am not aware of any such technology on the market, although
companies like Sonora Design could easily produce such a
stacker/destacker system. I too would like to get something like that
for the CATV system in my condo complex, but I need to accommodate the
stacked DirecTV signals already on the one cable.

Good luck!

Don
Jupiter, FL


wrote in
ups.com:

I'd like to combine the digital cable going to my Comcast digital CATV
box with the downlead from an OTA antenna. I want to combine the two
into a single coax, then split it again at the TV. The OTA split at
the TV will go to the RF input on my new HDTV with integrated HDTV
tuner to pickup the OTA digital signals, and the CATV signal will go
to the cable box. The cable box connect to the TV/monitor via HDMI.

That way, I can watch all the HD content from my cable provider via
the HDMI input, and also get the OTA digital signals the cable company
doesn't provide by simply changing the source I'm watching from on the
TV.

I know for satellite dishes this can easily be accomplished with a
diplexer on each end. I previously had DirecTV and this worked great.
But is there a similar combiner/splitter available for CATV?

Any help greatly appreciated.

CATV and OTA Antenna combiner/splitter
 

On Tue, 15 Aug 2006 15:14:21 -0700, cherrypicker wrote:

I'd like to combine the digital cable going to my Comcast digital CATV
box with the downlead from an OTA antenna. I want to combine the two
into a single coax, then split it again at the TV. The OTA split at
the TV will go to the RF input on my new HDTV with integrated HDTV
tuner to pickup the OTA digital signals, and the CATV signal will go to
the cable box. The cable box connect to the TV/monitor via HDMI.

That way, I can watch all the HD content from my cable provider via the
HDMI input, and also get the OTA digital signals the cable company
doesn't provide by simply changing the source I'm watching from on the
TV.

I know for satellite dishes this can easily be accomplished with a
diplexer on each end. I previously had DirecTV and this worked great.
But is there a similar combiner/splitter available for CATV?

Any help greatly appreciated.

It won't work because cable uses the same frequencies as OTA TV (it
doesn't work with the latest DirecTV Ka satellites for the same reason).