RadioBanter - View Single Post - A different way to reduce common mode noise,

Telamon · May 26th 07, 07:31 PM posted to rec.radio.shortwave

In article . com,
wrote:

On May 23, 10:03 pm, "
wrote:
On May 23, 6:26 am, wrote:

The burried 5/8' copper tubing circles our entire home.
The 4 corners all have 8' grounding rods.

All connections to the ground ring are Calwelded.

This is a suplamental to the required NEC ground.

The utility has the required 28' grounding rods.

The entry point for antennas and the mast for VHF/UHF
disk cone has a 8' ground rod and this is bonded
to the ground ring and the utility grounding rods per
the NEC.

The Dallas Lankford "15' Relay Switched antenna"s
each have their own 8' grounding rod, but becuase
there is no direct connection to the house ground
system. By "no direct connection", I mean the
secondary of the transformer is isolated with no
connection to the primary.

I changed "ground rods" to "grounding rods" at the
request of our commercial electrician.

Jesus H. Christ Terry, if I had to do all of this to keep my noise low
I'd probably give up radio! I used to work with the guy who
originally designed the Topaz high isolation xfmr. He's older then I
am (ancient!) but an expert on this stuff. I t doesn't surprise me
because I think most of the noise that gets to the radio is carried on
the AC line, either as common mode or in some cases differential mode.

Hey, if I had any sense I wouldn't be listening to SW in the first
place!

I got the idea to use the Topaz as an "ultra-isolation" transformer
from an experiment here atr work.

Snip

I've used them for low noise Faraday cage work. You have to filter all
lines in and out of the cage.

--
Telamon
Ventura, California