At 12:43 PM 6/21/2006, Jack Brindle wrote...

>The current evolution of the RS-232 spec also now contains a pinout  
>for an RJ-45 8-pin modular connector. ... RJ-45s allow much high panel density 
>that DE9  
>connectors, even though they have the problem of being the same as  
>those used for ethernet connections.

The current RS-232 spec, TIA-232-F-1977, only specifies the traditional DB-25 
and an alternate 26 pin connector.

The ANSI-TIA-EIA-723-1998 specification, which is more applicable to modern 
serial ports (RS-232-F only goes to 20 Kbps, "723" goes to 512 Kbps), adds the 
DE-9 connector.

Use of the 8 pin modular (RJ45 should not be hyphenated and refers to more than 
just the connector) is not defined in either spec. It is covered in EIA-561.

To the original concern, Elecraft chose a commonly available, easily used, 
reliable connector. It's not labelled "RS-232" or anything which would (should) 
lead someone to believe it's directly compatible. It's well documented. No 
problem.

BTW, an RJ45 doesn't actually exist, there are RJ45S and RJ45M telco 
interfaces. "RJ45" is an informal term incorrectly used to refer to 8 pin 
modular connectors.

All of this may seem a bit pedantic to those used to informal use of these 
designations, but in the standards world, correctness counts. It is through 
ignorance of the subtleties that incompatibility problems arise. Informal terms 
are fine, as long as everyone agrees. The problem quickly arises however, that 
not everyone does agree and being informal there is no authoritative reference 
to settle disputes. (from someone who's employer is a member/subscriber to 
most, if not all, communications/electronics standards organizations, and runs 
into this stuff regularly in real life situations)
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