It might. Electrical house grounds are notoriously noisy, although this is not such a big deal on VHF using one or another form of Frequency Modulation. A good outside ground will shunt current from the outer part of the coax shield to ground and reduce noise, but again this is of much more significance at HF. If you live in a lightning prone area you do need the shield of your coax grounded. For that purpose the house wiring ground will likely be just as good as a separate ground system outside your house.I have the cable going from my antenna-coax to a grounding block and then from there it goes into my house to my scanner. The grounding block has a wire going from it to the house ground. Is this ok to do and does it do anything to the reception?