HF Receiving Antenna & Grounds Question
 

Hi,

In the category of "why the heck didn't I do that years ago," thought I'd
relate my experience with a new HF receiving only antenna. Have a JRC 545.

Up to now, have had a simple random length wire running around the four
sides of my attic.
Worked, and was able to receive many stations, but was always disappointing.

Bought the PAR EF-SWL antenna, and just put it up outside as an Inverted-L,
and away from the house by
about 75 feet or so. Coax run-in to the receiver.
Wow, what an incredible difference.
The noise level is way, way down.

Question; The PAR ends in a Balun, from which I have a wire to a ground bar
I pounded into the ground next to it.
From there, the coax starts.

I also have a chassis ground from the radio to a nearby cold water pipe.
Have been putting it on and off trying to decide if it helps to have this
additional ground, or hurts.
There is of course the ground loop questions, etc. about having two grounds
(the earth ground by the Balun, and this one to the cold water pipe)

Hate to admit it, but am having trouble deciding if it helps.
At times, and for different freq's, I sort of think it
either helps, or makes no difference, at other time, perhaps a bit more
noisy.

Most of the time, I believe, it makes absolutely no difference whether this
chassis receiver ground wire is on or off.

**Anyone have any thoughts or comments regarding having this additional
ground ? **

Should it make a difference ?
I tend to think it shouldn't matter, as they usually suggest grounding the
coax, Also, right where it enters the house, which would
be pretty much equivalent.

There is, of course, also the grounding pin of the AC power line, which,
pretty much ends up at the same
place, namely a cold water pipe via a ground/neutral wire, from the AC
Service Box.

Curious about what all you experts think re these configurations.
Not too sharp with this, and would appreciate any thoughts on.

Thanks,
Bob

HF Receiving Antenna & Grounds Question
 

On Sat, 22 Apr 2006 07:52:09 -0400, "Robert11"
wrote:

Hate to admit it, but am having trouble deciding if it helps.

Hi Bob,

That pretty much defines it, then: no difference.

Should it make a difference ?

When you moved your antenna away from the source of local noise, your
house, that was the single most difference you could have expected.

There is, of course, also the grounding pin of the AC power line, which,
pretty much ends up at the same
place, namely a cold water pipe via a ground/neutral wire, from the AC
Service Box.

ALL grounds should go to that connection, even the remote one (and not
through the coax). The addition of that one won't make any DXing
difference, but it is code. It will prevent ground loops, whose
problems run from obnoxious to dangerous.

73's
Richard Clark, KB7QHC

HF Receiving Antenna & Grounds Question
 

Robert11 wrote:
Question; The PAR ends in a Balun, from which I have a wire to a ground bar
I pounded into the ground next to it.
From there, the coax starts.
**Anyone have any thoughts or comments regarding having this additional
ground ? **

Should it make a difference ?

You should always isolate the (poor) remote ground of an antenna used
for receiving from the station. There is no code that says it should be
connected to the station.
I isolate the grounds of my Beverage feedpoints from the feedlines,
even though they are thousands of feet from power lines.

The code problem is with grounds at your house, not with the ground at
the antenna. NEC requires all cables entering the house and all grounds
at the house to be bonded to a common point. You should not have a rod
outside for the hamshack ground that is not bonded to the utility
entrance ground. The logic behind this is any surges or lightning hits
will not elevate the two grounds to different potential, and create a
current path flowing through the house.

This is NOT a problem with the ground at the antenna, assuming that
ground is some distance from the house and you have a reasonable length
feedline to the house. What you should NOT do is float the station
without a ground, and you should not have the ground for the station
float independently from the service entrance ground.

If you see a noise change from adding a ground at the house it means
you have a feedline problem, radio problem, or balun or ground quality
problem at the antenna.

You might look at:

http://www.w8ji.com/noise.htm

73 Tom