The Difference Between RG6 & RG6Q

Both RG-6 and RG-6Q, or "quad" are deemed suitable for digital cable and satellite connections. Both have significantly higher capacity over longer distances than their smaller RG-59 cousin, using larger inner conductors and larger dielectrics. However, the differences between RG-6 and RG-6 quad are smaller than the differences between both of them and RG-59. Typically the two are only distinguishable by the markings on the jacket, unless insulation is physically cut away.

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The difference between RG-6 and RG-6Q is subtle unless the cable is dissected.

Inner Shielding

The key differentiator between the two cables lies with the inner shielding. RG-6 uses a single foil shield, covering 100 percent of the dielectric. This is surrounded by an aluminum braid. RG-6 quad uses two alternating layers of this foil and braid construction, making it virtually immune to external interference in normal installations.

Diameter and Thickness

RG-6 and RG-6Q share nearly the exact same outer dimensions and have similar flexibility. RG-6Q is slightly stiffer due to the increased amount of inner shielding, but does not present an installation challenge as a result.

EMI Interference and Signal Integrity

RG-6 quad is the preferred cable in any instance where moderate to high levels of electromagnetic interference may be a potential problem. RG-6 is completely acceptable in situations where the possibility of interference is negligible or non-existent. The carrying capacity over distance between the two cables, however, is virtually identical among the two cable types.