I think I remember this right.
If you have a long path to ground,
Use a piece of coax. Place a .01 mfd capacitor between the shield and
center conductor at the ground rod. Connect the rod to the center
conductor.
I think you only connect the center conductor to the station common ground.
Not exactly sure about the top connection.
This shields the ground wire, and prevents it from becoming a radiator.
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Bob Tinney
Sent: Saturday, February 20, 2016 8:38 AM
To: [log in to unmask]
Subject: Re: RFI question
Tom,
Either your long ground wire is causing a radiating ground loop or you've
got RF coming back down the shield of your coax. You could try a coax choke
at the antenna or try changing the length of your ground wire or try tuning
it, or try just disconnecting it
Bob, K8LR, [log in to unmask]
On 2/19/2016 11:43 PM, Tom Behler wrote:
> This is a multipart message in MIME format.
>
> ------=_NextPart_000_0010_01D16B6F.5C4D5990
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> charset="us-ascii"
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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
>
>
>
>
> ------=_NextPart_000_0010_01D16B6F.5C4D5990
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> 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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