[RFI] RFI suppression cores for 147 MHz

[Jeff Stevens]

On Fri, Mar 1, 2013 at 12:02 PM, Jim Brown <jim at audiosystemsgroup.com>wrote:

>
>   I don't work in the computer networking world, but I have seen shielded
> CAT5/6/7 patch cables. They are terminated with connectors that have a
> metal surround to mate with similar female connectors.
>

And that seems to be the easy part.  I've done runs with STP terminated
with metalized RJ-45s.   They are installed exactly the same way as
standard plastic connectors with the exception that the foil shield and
drain wire are placed in positive contact with the metal on the RJ-45
before crimping.


> Like ALL cable shields, it must go straight to the shielding enclosure at
> each end to be effective.


This seems to be the difficult part.  Core networking equipment (switches,
routers, etc.) is readily available which includes contact points to
connect the shielded RJ-45 to the device chassis ground.  On the other
hand, terminal equipment such as computers and networked printers virtually
never come with the appropriate contact points to accommodate a shielded
RJ-45.  Simply examine the NIC on any computer -- the grounding contact
points are missing.  This is what confuses me when people suggest the use
of STP.  What does one do to resolve the issue that there is no contact
between the STP shield and the terminal equipment chassis/ground?  I
suppose that the drain wire could be connected to the computer chassis
using a drilled and tapped screw but there has to be less labor intensive
off the shelf solution, no?  It's left me thinking that there is some
aspect of STP wiring that I don't understand.

-Jeff
W7WWA