Anybody can clarify if there would be an issue to have the Fido Internet and the TV Antenna connected to same Coax cable?
There would Definitely be a problem doing such. First of all, the Coax to your fido modem uses frequencies that should not mix with out side frequencies. Secondly, if you were to share the coax with a TV Antenna, you would risk leaking some of those signals intended for your modem into the airwaves, this could potentially cause unnecessary interference on wireless devices, appliances, and even neighbourhing cell towers because they use the same frequency range. I would advise AGAINST doing such and if you need to have an antenna and modem RUN A SEPARATE COAX CABLE.