1G requires all four pair. If you're getting a good 1G connection, your
pairs are electrically connected. If you have the pairs cross-connected,
you may still have issues. As an electrician you should be able to get
some network cable testers to make sure the pairs are right.
That's just one more thing to test.
Also, "name brand networking devices" doesn't help. The difference isn't
"name" and "no-name". The difference is "commercial" vs. "consumer".
On Sun, 11 Jan 2015, Jim Brown wrote:
On Sun,1/11/2015 8:35 PM, Wes Attaway (N5WA) wrote:
Network cable that isn't properly constructed with the required twisting of
wire pairs could introduce major RF problems.
Or RJ45 connectors that are improperly installed. CAT3, 5, 6, and so on are
PAIRED cables, and the pairs must be terminated in pairs (that is, to the
right terminals). For example, Brown and Brown/Wh is a pair, Orange and Or/Wh
is a pair, and so on. Twisted pair cable inherently resists coupling and
crosstalk of noise and RFI, and is at least as important than a cable shield
in that regard (and MORE important at HF and below). Each one of those
twisted pairs is a signal circuit -- but for that noise rejection to work,
they must be wires as pairs. Cross-wiring Bn/Wh to where Or/Wh should be
would defeat the benefits of twisting!
I know all stations have different situations, but I have run high and low
power off and on for many years with numerous routers and computers and
CAT-5 cables located within a foot or two of transmitters and have never
had
a problem with anything.
Proximity of wiring or victim electronics to transmitters is not what matters
-- it's the proximity to ANTENNAS, because they are what radiate the RF.
I think there is something going on other than CAT5/router issues. What
about the house wiring, your coax connector soldering, station grounding?
A connection to the EARTH is rarely part of a solution to hum, buzz, or RFI.
Rather, BONDING is important, and so are Pin One Problems. Proper grounding
and bonding for ham stations is addressed in this tutorial.
http://k9yc.com/GroundingAndAudio.pdf
Do you notice any other RFI ill-effects other than the CAT5/router issues?
Some DSL systems are notoriously susceptible to RFI. AT&T Uverse is one of
them. Bud, W2RU, author of the "Practical Antenna Handbook," went through
some serious work to cure the RF to his DSL from his 160 and 80M operation.
I recall exchanging email with him, and also seeing reflector posts from him.
73, Jim K9YC
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Hisashi T Fujinaka - htodd@twofifty.com
BSEE + BSChem + BAEnglish + MSCS + $2.50 = coffee
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