Coaxial cables, usually identified by "RG" and a number, carry a wide variety of electronic signals for thousands of applications. The signal travels over a center conductor surrounded by an insulating material, a shield made of foil or woven copper and an outer protective jacket. RG60 and RG59 are close in their number designations but not in characteristics.
Impedance
The impedance of a coaxial cable tells how much opposition it presents to a signal source. RG59 has an impedance of 75 ohms and RG60, 50 ohms. Most lower power circuits operate at 75 ohms and higher power circuits at 50 ohms. Although there is no exact power trade-off point, 50-ohm cable more frequently carries transmit signals and 75-ohm carries received signals. RG59 is used extensively for lower power signals in home entertainment and industrial telecommunications systems. RG60 is not commonly used and is difficult to find. People could easily confuse RG60 with RG6, an entirely different cable.
Impedance Mismatch
Mismatching impedance by using a 50-ohm cable on a 75-ohm circuit or vice versa can cause signals to reflect between the source and the destination, causing standing waves and excessive power loss at different frequencies. A television signal reflected in a cable can cause ghosting. Although most home entertainment system components don't readily show impedance statistics, they are usually 75 ohms. Sometimes manufacturers recommend certain types of coaxial cables, including RG59 and RG6, but not RG60. You should not use a cable known to have 50 ohms of impedance in your TV system.
Physical Characteristics
RG60 is thicker than RG59 and almost five times heavier, weighing 15 lbs. for a 100-foot piece. The same amount of RG59 only weighs 3.2 lbs. RG60 has an outside diameter of 0.46 inches and RG59 is 0.24 inches. Both have a braided copper shield. RG60 has an insulation thickness of 0.25 inches and a 0.05-inch center conductor. RG59 has 0.15 inches of insulation and a 0.03-inch center conductor. RG60 has a rubber outer jacket and RG59 one of PVC. Both can withstand temperatures between -40 and 176 degrees Fahrenheit.
Military Spec Equivalent
Under military specifications category MIL-C-17, the Department of Defense defines technical requirements that coaxial cables must meet for military use, classifying RG59 as M17/29. Cable manufacturers strive to meet these specifications for all types of coaxial cables. One hundred feet of RG59 should have no more than 9 decibels of loss at 400 MHz, and no more than 16 dB at 1,000 MHz. RG60 has no military specification equivalent and its exact technical characteristics are not clearly defined. Specifications for RG6 (M17/2) however, show a 75-ohm cable with lower loss than RG59 that would work well for TV and satellite antennas.
Tags: center conductor, 50-ohm cable, coaxial cables, home entertainment, lower power, more than, power circuits
