Tom, you might want to consider inserting a common mode choke in your
feedline. Also, do you have a coaxial choke in your feedline, e.g. five or
six turns of about 5 inches in diameter where your feedline connects to your
antenna?
Ron, K8HSY
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Tom Behler
Sent: Friday, February 19, 2016 10:44 PM
To: [log in to unmask]
Subject: RFI question
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Hello, everyone.
I know I'm going to get a lot of different opinions on this question, but
here goes:
I have been noticing lately that my RFI problems seem to be getting worse
here at the home QTH.
In particular, they seem worse when I'm on CW, and appear on different bands
to different degrees. The fact that the problems seem worse on CW does not
surprise me, due to the nature of that mode in comparison to SSB, for
example.
What does baffle me is that the problems seem to be getting worse in
general.
For example, when I was playing around a bit in the ARRL International DX CW
contest for an hour or so tonight, I tried going back to a few stations with
approx. 500 watts, using my MFJ998 and ALS600 with the TS590, and I set off
the carbon monoxide detector downstairs on the main floor of our house. On
another occasion earlier in the month, I was running 100 watts on CW on 160
meters, and I tripped one of the circuit breakers in our house, and caused
my wife problems when she was using her laptop computer in another room.
I have checked the common ground point on my MFJ feed-through panel, and the
ground cables for my TS590, MFJ998, and ALS600. All seem to be solid, at
least here in the shack. The common ground point on the MFJ feed-through
panel has a cable outside my second-floor shack window that runs down to a
copper ground rod that is connected to the ground on the power box to the
house.
I have not checked the outside ground connections at the ground rod, and may
try to do that tomorrow.
My initial thinking is that RF is either coming through the house electrical
lines, through our cable modem and router, or both.
I am planning on investing in some RF chokes as Steve (KW3A) has suggested,
and possibly one or two Buxcom Line Isolators like Butch uses, but am
wondering if I'm missing something obvious that I should check into first.
Any thoughts would be appreciated.
Tom Behler: KB8TYJ
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</o:shapelayout></xml><![endif]--></head><body lang=3DEN-US link=3Dblue =
vlink=3Dpurple><div class=3DWordSection1><p class=3DMsoNormal>Hello, =
everyone.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
class=3DMsoNormal>I know I’m going to get a lot of different =
opinions on this question, but here goes:<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>I have been =
noticing lately that my RFI problems seem to be getting worse here at = the
home QTH.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
class=3DMsoNormal>In particular, they seem worse when I’m on CW, = and
appear on different bands to different degrees. The fact that = the
problems seem worse on CW does not surprise me, due to the nature of = that
mode in comparison to SSB, for example.<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>What does =
baffle me is that the problems seem to be getting worse in =
general.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
class=3DMsoNormal>For example, when I was playing around a bit in the = ARRL
International DX CW contest for an hour or so tonight, I tried = going back
to a few stations with approx. 500 watts, using my MFJ998 and =
ALS600 with the TS590, and I set off the carbon monoxide detector =
downstairs on the main floor of our house. On another occasion =
earlier in the month, I was running 100 watts on CW on 160 meters, and I =
tripped one of the circuit breakers in our house, and caused my wife =
problems when she was using her laptop computer in another =
room.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
class=3DMsoNormal>I have checked the common ground point on my MFJ =
feed-through panel, and the ground cables for my TS590, MFJ998, and =
ALS600. All seem to be solid, at least here in the shack. = The
common ground point on the MFJ feed-through panel has a cable = outside my
second-floor shack window that runs down to a copper ground = rod that is
connected to the ground on the power box to the = house.<o:p></o:p></p><p
class=3DMsoNormal><o:p> </o:p></p><p = class=3DMsoNormal>I have not
checked the outside ground connections at = the ground rod, and may try to
do that tomorrow.<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>My initial =
thinking is that RF is either coming through the house electrical lines, =
through our cable modem and router, or both.<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>I am = planning
on investing in some RF chokes as Steve (KW3A) has suggested, = and possibly
one or two Buxcom Line Isolators like Butch uses, but am = wondering if
I’m missing something obvious that I should check = into
first.<o:p></o:p></p><p class=3DMsoNormal><o:p> </o:p></p><p =
class=3DMsoNormal>Any thoughts would be appreciated.<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p><p class=3DMsoNormal>Tom Behler: =
KB8TYJ<o:p></o:p></p><p =
class=3DMsoNormal><o:p> </o:p></p></div></body></html>
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