Thanks Jim for your input. I will have to study your presentations in
more depth. Years ago, I worked building audio amplifiers and tape
duplicators that also had a small oscillator for some AC bias needed for
tape recorder recording heads. Ground loops at the time were always a
concern and we had to make sure that we only grounded the entire system
at one point to the chassis, and ran a ground rod suspended down the
center of the chassis and grounded all components to that ground rod.
I noticed in one of your slides that you said to NOT run the tower
grounding system back to the house AC input ground if it is too long
(but to depend on the antenna coax sheath). How long is too long?
It is about 40-50' from my shack wall to the tower base, but probably
100' from the tower base to around the other side of the house to the AC
input of the house (house ground rod). I am planning on putting in about
9 ground rods around the base of the 73' tall crank-up tower (3 off of
each leg in a "Y" configuration). The first rod off of each Y leg will
have a wide copper strap connected from the ground rod to the tower leg
in a gentle arc with no sharp turns. Most installations I've seen have
maybe a 3" or 4" wide piece of copper. All three Y base leg ground rods
will be cadwelded to #2 copper stranded in a ring around the tower. It
was this ring that I was going to run to the AC house ground rod.
Finally, the other 2 ground rods in each Y configuration were planned to
be cadwelded to the base leg of the Y with #2 stranded. Any comments? PS
- We have heavy clay soil here in NC.
Dick, K0CAT
=======================
Jim Brown wrote on 7/24/2016 2:07 PM:
On Sun,7/24/2016 9:04 AM, Dick Blumenstein wrote:
one huge ground loop.
Ground loops are a massive fiction, a completely false concept. Here's
my take on power, grounding, and bonding for hams.
http://k9yc.com/GroundingAndAudio.pdf
And here's my comparable work for professional audio and video, which
I taught for ten years at conventions for audio and video contractors
who build systems from the small to the very large. The first link is
to a long tutorial, the second two are to Power Point slides for my
workshops.
http://k9yc.com/SurgeXPowerGround.pdf
http://k9yc.com/InfoComm-PowerSystems2012.pdf
http://k9yc.com/InfoComm-Grounding2012.pdf
73, Jim K9YC
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