What is the difference between rg6 rg6u rg6 quad and rg6q?

Answer 1

RG6 specifies a family of co-ax cables with similar characteristics. Within the family, there are several variations such as the materials used, screening and other characteristics. To select the right cable, there is no alternative to looking at the data sheets supplied by all manufacturers.

Remember that there are quality variations between manufacturers, so if you can't get a data sheet from a supplier, look elsewhere. All of the better quality suppliers will be happy to provide a data sheet. Those who won't give you a data sheet may have something to hide or simply don't know the performance of their own cable.

RG6 quad just means 4 layers of the thin silver insulation. The difference between rg6 and rg6 quad is negligible.