[Elecraft] Update on my progress - Now General RF Issue WAS 160m loop experiment a big failure

[Ken Alexander]

Thanks Don, and all who contributed to help him.

Yours has been an interesting story and it was educational to watch it 
unfold here.  I bet the CQ or QST would eat up a story like that if it 
was well documented and turned out as well as yours.

Regards,

Ken Alexander
VE3HLS

On 23/10/2011 9:13 AM, goldtr8 at charter.net wrote:
> First, let me say thank you to everyone on the list who has replied via
> the list or directly.   The help has been fantastic and has increased my
> general knowledge as well as helping me with the problem.
>
> Althought I have pointed to the start of the problem with the
> installation of the Loop and the install of the propane tank and
> possible crushed coax, I now believe that I have always had some RF
> issues but it was brought to my attention by the Loop being real bad and
> then I was highly sensitive to the whole system.
>
> First I had made a significant error in the basic grounding of my shack.
> This error I will call the green wire mistake.  What I had done was add
> the chassis ground of all my 12v devices  and tuner to the green wire
> ground of the house electrical system.  This is in fact a signficant
> error and has been corrected.  What I have learned that there is a
> difference for a saftey ground for lightening protection and so on and
> it has nothing to do with an RF ground.  So green wire error fixed, long
> term a total revamp of the system for a safety ground.
>
> Second I did a lot of checking of the coax yesterday.  Checked it with
> nothing attached, checked it with a dummy load, used functions of my MFJ
> 259b that I did not even know existed.  Basically the coax checks out
> fine, but I still have RF.   The coax at this point in time is no longer
> buried, I completely unearthed it.
>
> At this point in time I put a choke at the antenna feed up in the air
> with 31 mix ferrites and no improvement.  So if the problem is at the
> antenna feed this should have fixed it.  I remove my lightening arrestor
> from the system just to check it out no change.  So I pull the choke
> down.
>
> Next I put a choke right at the antenna out the same choke that I had
> put on the antenna feed point.  Wow big improvement plus I added more
> snap on 31 ferrites directly on the coax.   So I have a choke in the
> shack and now I can go full power.   So having the choke at the feed
> into the antenna tuner has a dramatic effect.
>
> Now I am thinking ok I will burry the coax again, easy to do in the soft
> grass plus I want to see if the problem turns on again as I have changed
> the system with the coax laying on the ground and the outside is dry not
> directly coupled to the set ground.  After the burry RF is bad real bad.
> So coax is now on laying on the ground again unearthed and the system
> again functions, points again to bad coax.
>
> I am now convenced that this is it so I turn on the shack PC to get some
> more information and so on.  Plus I am talking to some other hams on
> what I have found.  As the PC boots up the RF is back and it is strong.
> Holy Sxxt Batman, now what.   So I ponder this for a moment, since I
> removed my geen wire error the PC is no longer connected to the K3 than
> thru the rs232 so I am assuming Pin1 problem.  I make a ground wire from
> the chassis of the PC to the center of the grounding point (grounding
> star as it is referred to) and fixed.  So I take a critical look at the
> PC installation and the coax runs right next to the PC.  So I disconnect
> everything and move the PC to the other side of the desk to get it as
> far away from the coax as I can plus this eleminates short jumper cables
> for the mouse and so on.  So other than a brief instant when the PC
> boots up and it is a very specfic part of the boot cycle there is no RF.
>
> So in a nutshell
>
> 1) fixed green wire problem
> 2) unearthed coax and it is laying on the ground on the top of the grass
> 3) build choke with 31 mix at antenna out on the tuner
> 4) moved PC
>
> I am on the air.
>
> To do when the order shows up from UPS.
>
> Install new coax, I assume the one I have is not happy anymore and test
> the system to see if I can remove the choke at the tuner.
>
>   From my perspective I am on the air, but I do not have a robust
> installation being on the 2nd floor.  I probally can survive this winter
> this way with the simple antenna shield grounding outside as I did last
> winter as there is no lightning normally.  However, I have to determine
> the best way to redo the installation and am considering moving the
> shack to the basement where then it will be signficantly eaiser to have
> the shack properly grounded for safety and then bonded.
>
> Again thanks for the help, as I am on the air but not convinced that I
> have it fully cured.  So there may be more questions in the future when
> I find stuff starts to not work again.
>
> ~73
> Don
> KD8NNU
>
>
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