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 Post subject: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 7:57 pm 
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Location: Poulsbo, Wa
I have been able to run a long wire ( random wire) outside about 200 feet. I had grounded it through the house wiring and that made it worse but then i ran a wire directly to the ground rod and that was much better static wise.

Can i run an insulated random wire and the insulated ground wire next to each other in the house (like right on top of each other) for about 40 feet to get outside or will i create a dipole or other problems? I have one way in and one way outside.

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Bill


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 8:12 pm 
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Yes, both wires can be next to each other. I am not sure what effect it would have, not a lot. Perhaps having the lead in in house say 20 feet for example making the antenna like 180 vs 200 feet.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 8:21 pm 
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poulsbobill wrote:
Can i run an insulated random wire and the insulated ground wire next to each other in the house (like right on top of each other) for about 40 feet to get outside or will i create a dipole or other problems?
You can definitely run your antenna lead and ground next to each other. Most who do this would probably use TV Twin Lead or TV Window Line for this purpose. It could run you around a $.50 to $1/foot. You could also try speaker wire which might work OK but perhaps not as well (not sure if you would notice the difference on receive but for a transmitter it would be a definite No-No).

Technically twin lead is a better impedance match for a long wire antenna which tends to be a non-resonant high impedance antenna. The speaker wire presents a significant impedance mis-match, but for receiving purposes in might prove to be acceptable.

It would be best if your feed line did not sit too close to any other metal (2 or 3 inches should be fine). Being too near other metal causes losses.

Best of luck.

Curtis Eickerman

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 8:30 pm 
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Hello Curtis, how about using a length of coax cable? Would you say twin-lead is better or no diff?

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 9:17 pm 
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I started out with 25' of 300 ohm twin lead going from inside the house out to my antenna wire and ground rod. It's easy to run under a window sash. But it will pick up more electrical noise in and around the house than using something like 50 ohm coax and a balun.


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Fri 10, 2020 9:36 pm 
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Location: Utica, NY 13502 (USA)
My antenna is about 200'. There is a ground rod at the near-end of the antenna. From there, both the antenna lead and ground lead from the ground rod are fed to the house 50' underground suspended next to each other inside rigid, 2" PVC plumbing pipe. The suspension points are at the ends and every 10' where the pipe sections connect. The wires are spaced about 1/2" apart at those points. Works great with very little noise pick-up but the efficiency drops off rapidly above about 18 MHz. Works best when connected to A1 and A2 terminals on radios that have a balanced input.

Dave


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sat 11, 2020 12:14 am 
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westcoastjohn wrote:
Hello Curtis, how about using a length of coax cable? Would you say twin-lead is better or no diff?
Yes, you can also certainly use coax cable. It generally runs a little bit more money, but should work just fine. It can be used with or without a balun. Again, things like baluns and impedance matching are much more of an issue for transmitters than for receivers.

Curtis Eickerman

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sat 11, 2020 2:20 am 
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This is going over my head (nothing unusual); why would you ground an antenna wire?

I have a 240' random length long wire on my back acre. The lead-in is RG-59 coax, center conductor. The outer shield isn't connected to anything, but is just presumably to fend off house electrical noise. Works just fine.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sat 11, 2020 11:56 pm 
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When i have grounded the radio i find that the static goes down.
You will find that w/o a balin your signal will go down if you ground that coax and ungrounded really does nothing. ( so i have read).
.
With that said the reason i had asked the question was when i had tried this with a ac wiring ground (ie house ground) i actually added static to my feed. So is i use a clean ground source (ie a new dedicated rod) running the wire next to my antenna will be ok?

Thanks

Bill


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sun 12, 2020 1:11 am 
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poulsbobill wrote:
When i have grounded the radio i find that the static goes down.
You will find that w/o a balin your signal will go down if you ground that coax and ungrounded really does nothing. ( so i have read).

There's a difference between reading what others have said and found in their own experiences, and trying it yourself.
Trust me, I did try both grounding the coax shield, and using a balun, and in both cases, really found no difference in reception ability, or noise floor.

poulsbobill wrote:
With that said the reason i had asked the question was when i had tried this with a ac wiring ground (ie house ground) i actually added static to my feed. So is i use a clean ground source (ie a new dedicated rod) running the wire next to my antenna will be ok?

Thanks

Bill

Your question is IF I use a clean ground source; my answer would be to try it. What worked or not for others may be different for you.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sun 12, 2020 12:08 pm 
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What "fifties" said is very true. There is no cut and dried answer to good reception. What works for one person, doesn't work for the next. Same goes for one radio to the next. I started out keeping a 3x5 card on the back of my radios about what worked best for each. Eventually, I ended up with a lot of tricks to try.


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sun 12, 2020 4:04 pm 
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Location: Fenton, MI 48430
poulsbobill wrote:
When i have grounded the radio i find that the static goes down.
You will find that w/o a balin your signal will go down if you ground that coax and ungrounded really does nothing. ( so i have read).
.
With that said the reason i had asked the question was when i had tried this with a ac wiring ground (ie house ground) i actually added static to my feed. So is i use a clean ground source (ie a new dedicated rod) running the wire next to my antenna will be ok?

Thanks

Bill

I use water distribution pipes as a ground. All copper pipes. Very quiet ground.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Sun 12, 2020 4:23 pm 
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Any single long wire antenna is in reality only 1/2 of the antenna system. The RF current from signals needs a return path, or some sort of counter poise for best efficiency.

If you do not use a separate dedicated ground rod, or similar, the return path will be through the house wiring. In some cases it will be adequate.... BUT!!! depending on the number of noisy switching supply wall warts and other noise generators on that branch circuit you could end up with copious amounts of RF noise being coupled right back into your antenna system. Sometimes the AC service ground rod mitigates the problem, sometimes it doesn't.

Even with a two wire AC system, the signal is still capacitivity coupled back to the AC wiring. If you have noise, then try an external ground to see if there is any improvement.

A really cheap substitute for 75-ohm CATV coax is a run of CAT-5 wiring. Any pair will be close to a 75 impedance, and the twisted pairs are self shielding.

Pete

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 12:30 am 
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I have been testing different grounds, and like said it "depends".
I have used my long wire as a counterpoise for a loop i had made. It worked nicely (really reduced static)
but i still dont get enough signal from a loop. ( at least not as much as the 200' random wire). I used them together loop and long wire and was tunable to a degree. Want to try a good ground with that one.

I've ran a dedicated ground wire 80' bypassing the ac gound all the way to my house ground and it was very clean.

I have used the house wiring and found it either noisy or had little effect.

But on different days the results were different except the 80' to the house ground is always good.
So i am running a much shorter ground wire to a new ground rod i bought. Does gauge matter here?
I know for an antenna size (girth) doesn't matter but for a ground?

Thanks

Bill


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 12:58 am 
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Describe please what is the loop in use?

How is the loop configured to interact with the receiver?

Is the loop intended for Broadcast reception or is shortwave involved as well?

How is the home constructed, is there concrete or masonry walls or is there a metal foil vapor barrier, metal siding?

Mitigating factors will cause a loop to fail. Some simple steps such as locating the receiver near a window will help as well as experimenting coupling the loop to the receiver. Manufactured loops do not offer a large capture area and often have a self-resonance that effects reception in part of the BC band. If a loop cannot be made to resonate at the desired reception frequency, it serves as a simple loading coil. If the area surrounding the loop is subject to electrical noise, the untuned loop will simple introduce more noise...

I find 80' to an earth ground a problem. A location in a high rise would be an example where an earth ground would be 80' or much more. In such a situation a counterpoise is used.

Defined here: https://en.wikipedia.org/wiki/Counterpo ... und_system)

The ground wire to the receiver need be only big enough to withstand corrosion effects.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 1:45 am 
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As Chas asked, please describe your loop. Mine is 23" in diameter, and is essentially the same AFA RF gain, compared to my 240' long wire.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 8:17 am 
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Use an amplified (power fed over 50' of coax) untuned Mag Loop myself. Very good on all bands but I'm not much of a shorth wave listener.

Gary


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 4:38 pm 
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I built this loop https://earmark.net/gesr/loop/amloop2.htm
Does work well, just not as well as the 200' random wire. Again together they work well.
200' of random wire does reduce static from the loop when used as a ground.

I use a pick up loop on the main loop to connect to the 1936 1937 zeniths which only rec longwires.



Bill


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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 7:41 pm 
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poulsbobill wrote:
I built this loop https://earmark.net/gesr/loop/amloop2.htm
Does work well, just not as well as the 200' random wire.

This is a perfect example of what works for one doesn't mean that it'll work the same for someone else. As I had stated, in my case the 23" loop gives equivalent performance to my 240' longwire. Could be it's round shape is better than a square one, IDK.

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 Post subject: Re: Long wire ( random wire) and ground proximity
PostPosted: Jul Mon 13, 2020 8:38 pm 
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Does the O.P.'s loop resonate across the BC band?

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