Coax Cable Nomenclature

[Howard James]

Can anyone let me know what the suffix A; B; C means in coax type number
such as RG59B/U?
I know the /U stands for standard i.e. foil not copper shield but I can't
find anything on the B etc.
Thanks.
Howard.

[Crazy George]

This nomenclature system was developed here in the colonies by our Dept. of
starting things they can't finish back about 65 years ago. RG stands for
radio guide, if that identifies the time frame any for you. First, let me
say that particular system RGnnn/xyU has been obsolete for 30 years and the
letters can mean anything you want them to. In the US, the only system
which is presently supported by any semblance of standards is the
M17/NN-nnnnn nomenclature.

The /U means utility i. e. not assigned to any particular system, otherwise
it would be /FRR or /APN, some such, with the letters identifying the class
of system.

As far as RG59 is concerned, RG59/U has a braided bare copper shield, as do
RG59A/U and RG59B/U. The difference in the cables is in the jacket (A=
PVC-1, B and C=PVC-2) and the impedance (73 ohms for 59 and 59 A, 75 ohms
for 59B). Nowhere in the MIL-C-17 specifications for RG59 is foil shielding
mentioned. But, again, these last specs are over ten years old, and apply
to cables fabricated before 1990. Anything goes now. You can wrap paper
towels around carbon string, put cabbage leaves on the outside, stamp it
RG59C/U and no one can challenge it.

Do a Google search for US DOD MIL standards and look for MIL-C-17, which is
mind numbingly long, but has every answer about coaxial cable you could ever
want to know. I use a microfilm copy in the company library, so I am not
sure what the URL is.

--
Crazy George
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