While all RG cables of a certain name may be the same size, RG does not define construction standards of even materials in many cases. In the Ham and Amateur Radio world RG continues to be used mainly to define cable size and type due to the years it was an accepted standard. These types of coax cable were once all listed in the MIL-HDBK-216 which is now obsolete and has been replaced in military use by newer design specs.
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