I'd like to comment on ground also.
My shack is in a separate building, and since its "the shack" I can
make holes in the walls anywhere I want ! :))
So, I have a hole right behind the rig, going to an array of ground rods
right below the hole. Some 5 feet of length in all. Wonderful ground.
But its still not good enough for 6 meters for example. So, I placed a
second heavy line in parallel with the first, but much longer. This way
I get the low impedance point to repeat at the shack end of the line.
No way is this a new trick, but its worth recalling.
73 de Gary, AA2IZ
----- Original Message -----
From: "Robert & Linda McGraw K4TAX" <RMcGraw@Blomand.Net>
To: "Stuart Rohre" <rohre@arlut.utexas.edu>; "Rob Atkinson K5UJ"
<k5uj@hotmail.com>; <tentec@contesting.com>
Sent: Wednesday, October 09, 2002 11:10 PM
Subject: Re: [TenTec] Omni VI+ and Heil mics
> Stuart:
>
> I agree totally with your comments.
>
> With one point of clarification:
> Most of us have shacks too far from RF ground. Keep in mind that RF
ground
> is based on electrical wavelength. Hence a ground that is 1/4 wavelength
> produces the highest voltages at one end. Example: on 20M 1/4 wave is
some
> 16ft. and is a worst case situation for an effective RF ground on 20M.
>
> I use balanced feedline on a center fed 256 ft. wire and operate 160M -
10M
> and have NO RF ground on the rig or tuner. There's no RF in the shack
> either. The only ground is the AC 3rd pin ground for safety purposes. My
> station is on the 2nd floor of a wooden frame house. Under these
> conditions, the Omni VI+ driving the Centurion amp doesn't cause a
problem.
> Clearly my balanced feed system works and the center of the antenna is 55
ft
> above ground. Also, there is no telephone interference or TVI either.
>
> 73
> Bob K4TAX
>
> ----- Original Message -----
> From: "Stuart Rohre" <rohre@arlut.utexas.edu>
> To: "Rob Atkinson K5UJ" <k5uj@hotmail.com>; <tentec@contesting.com>
> Sent: Wednesday, October 09, 2002 9:50 PM
> Subject: Re: [TenTec] Omni VI+ and Heil mics
>
>
> > Rob, I think many of those who report hum problems need to look to their
> > grounding practices, since you demonstrate none of the problems. There
is
> > no great difference in the audio circuits of the models, as far as it
has
> > been told here.
> > Many expect to run with Windom type, (unbalanced) antennas or even end
fed
> > or random wires and then are surprised they have RF in the shack. Most
of
> > us have shacks too far from earth to have effective RF grounds to an
earth
> > rod only.
> > 73, Stuart K5KVH
> >
> >
> > _______________________________________________
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> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>
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