| > RJ-45 (really RJ-38 but that's excessively pedantic) connectors If we're being overly pedantic: - the RJ numbers refer to not just the connector but the pinout and such - the RJ (registered jack) numbers refer to just the "jack" side, not the "plug" side So even though an "Ethernet" cable has plugs on it that fit into an RJ38X jack, its wrong as well to call it an RJ38 plug: - different pinout - the plug is the mechanically the same, but pedantically it isn't correct to call any plug a registered jack, because it's a plug not a jack - the jack is mechanically different; an RJ38X jack shorts pin 1 to pin 4 and pin 5 to pin 8 when there's not a cable plugged in to it (this makes it a "series jack" instead of a regular "jack"). Name | Mechanical jack | Mechanical plug
47 CFR part 68 (registered jacks)
RJ45S | miniature 8-position keyed jack | miniature 8-position keyed plug
RJ38X | miniature 8-position series jack | miniature 8-position plug
ANSI/TIA-568 (Ethernet)
T568A | miniature 8-position jack | miniature 8-position plug
T568B | miniature 8-position jack | miniature 8-position plug
I don't believe any registered jack uses a miniature 8-position unkeyed jack (but scanning through 150 pages is a pain and for some reason Ctrl-F isn't working reliably in this PDF).(ANSI/TIA/IEC calls them "modular" jacks/plugs, while the FCC calls them "miniature" jacks/plugs, but same thing. Well, same thing the way that CAT-5 and CAT-5e are the same; same, but with different specified tolerances. And just saying "Ethernet" or "568" isn't specific enough here; CAT-6 requires an IEC 60603-7-4 connector, while CAT-5e only requires an IEC 60603-7-2 connector; even though most people would call those the same, they have different tolerances. I don't care to compare the FCC's 47 CFR part 68 requirements with the IEC 60603-7-{2,4} requirements.) |