Hi all.

I am trying to modulate about 5 channels onto an RG6 cable that carries a Time Warner Digital Cable signal (as well as roadrunner).

This handy table shows me the frequencies of standard UHF/VHF channels.
http://www.csgnetwork.com/tvfreqtable.html

I am trying to figure out which frequency band carries a) the digital information and b) the cable modem information. I want to make sure as I notch out space for my modulated signal, I don't step on anything that is used for digital.

I initially wanted to be in the 750mhz range (channels 110 or so) because those seem to carry no information to my regular TVs (no cable box), but am not quite sure that is true.

Thanks in advance,
--rick

You may find it easier to low pass filter the CATV feed below the highest signal of interest, than to notch out individual or blocks of channels in-band. The filters available to end users for that mode are cheaper and more readily available.

The typical TWC band plan (but it varies from system to system) is analog channels from 54-555 Mhz (channel equiv 2-78 or so), then digital services as 6 MHz QAM channels from 555 to about 712 MHz (channel equiv 80-110 or so, but if your system is newer it may go up to 802 MHZ or channel 125 equivalent). You can determine the frequencies in use on your system from the diagnostics page of the SA set top box.

On our headend, the cable modem downlink is on 555MHz (CATV ch 79) and the uplink is in the subband at 23 MHz (return path channel T-9 equivalent). Your cable modem data (browse to its IP address 192.168.100.1 typically) will tell you what the up and down frequencies are in use in your system.

Hope that helps...

Mike