Canadian TV, Computing and Home Theatre Forums banner
1 - 1 of 1 Posts

5,192 Posts
I think Cable TV Frequencies in North America can go up to 1 GHz.

Satellite TV IF frequencies for legacy FSS and DSS bands, start at 950MHz (950 - 1450 MHz).
So there may be some overlap if ya used a pair of Satellite / OTA Diplexers.
I suspect some of the more advanced satellite systems might even have more spectrum
coming down the coax from the dishes these days. I am not familiar with them all.
(eg band stacking feeds, etc.).

I think I would login to my Cable Modem and determine exactly which RF Channels they are using for the Internet service. On my Motorola Surfboard modem, I login to
to see the RF Frequencies and their current SNR (signal quality). Yours may be different, but google it.
For reference, in the downlink mine are:
705,651,657,663,669,675,681,693 MHz
all ~ 38 to 39 dB SNR.

Your Cable System's Freqs will certainly be different, but their SNR should be up there in a similar range. If yours are significantly lower in SNR, that might explain some of your issues.
Further, If I were to change anything related to the cable modem's rf path I would want to take
a peek at the SNR readings in my modem before and after the change to be certain that I didn't degrade the signal quality at all in the process.

3700-4200 MHz
5150 MHz LO
IF = 950 to 1450 MHz

Ku FSS Band
11700-12200 MHz
10750 MHz LO
IF = 950 to 1450 Mhz

12200 - 12700 MHz
11250 MHz LO
IF = 950 to 1450 MHz
1 - 1 of 1 Posts