Looks good, Reed - think you got it set just right.
Grounds are most confusing to a lot of guys because there are three of them
to be considered: a-c safety ground; "r-f station ground;" and lightning
ground.
The problem is that grounding is like pregnancy - most guys do just a bit of
it and feel comfortable when in reality it takes a major effort to achieve
anything close to an effective r-f ground, if indeed one can be achieved at
all in a given location. An 8-ft copper rod into the ground just isn't a
low-impedance connection to "earth" and the means used to connect it to the
station just increases the impedance unless a tuning arrangement is used.
Usually most shack r-f comes from having the equipment in the near field of
the antenna system. Best result there is to use a driven ground: a 1/4 wave
wire with one end insulated and the other end connected to the station
"ground" point, usually the tuner chassis. Being in the near field induces a
current in the wire which, since the open end is floating, drives the
station-=ground end to near zero r-f potential. This is usually far more
effective than any effort at an ohmic "connection" to "earth."
If your shack is to code, the a-c safety ground will be taken care of. If
you use antennas that do not include the station tuner and transmitter as
part of the antenna system - end-fed longwires, for example - then
everything in the station will assume the same r-f potential (zero or
otherwise) and little trouble results IF care is taken to prevent
common-mode current from entering the shack via the feedlines. Lightning
ground is a whole other world - that one is for the experts. But I have
never in 58 years used any kind of ground system - r-f or lightning - and
never have had any problems. I keep things disconnected during storms and
that opens the majority of the paths that a discharge could take to get to
the equipment. I use antenna systems that do not include the equipment as
part of the system and keep the feedlines clean. Seems to work.
This is a very controversial topic which I have given up debating in public
so my remarks are intended for your eyes only! <:}
Hope you can pin down the 17 and 20 meter situation. Bound to be a reason
there somewhere!
73/72, George
Amateur Radio W5YR - the Yellow Rose of Texas
Fairview, TX 30 mi NE of Dallas in Collin county EM13QE
"In the 57th year and it just keeps getting better!"
<mailto:w5yr@att.net>
----- Original Message -----
From: "Reed" <w4jz@ispwest.com>
To: <tentec@contesting.com>
Sent: Sunday, August 10, 2003 7:29 PM
Subject: [TenTec] Argo Speech Processor Question (was Argo V distortion)
Well George, the Windom & Beam have 1:1 Balun at the antenna feed point.
Like I said before I can't hear it on the antenna or dummy load. But, other
stations can on 17 & 20 meters with SP on. Strange, glad I'm a CW operator!
On the ground, I have to agree. At my other QTH I had a very good ground
system (8 foot ground rod 6 feet of #8 wire)& had more problems getting into
the phones, cable TV, & I can't count the times that during a storm I would
have lighting come in on the coax to the tuner which was grounded. Could
hear all kinds of popping going on inside the tuner. Always kept the rig
disconnected. Have the same setup here, but no ground & I'm on a very high
hill. I also don't get into the phone or cable.
My late father, W4PFP, was a state electrical inspector for over 30 years &
he told me that they discovered that more strikes come from the ground up
than from the sky down.
I had word wrap on, but decreased it from 78 characters to 60. See what
this does.
Thanks,
Reed
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