guardrail as HF antenna

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tikkis

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hi.

i have a question to you pepole.
i have little space to setup an HF antenna.

but 10 meters from my house there is a gurad rail that is aprox 100meters+ long. can i use that as a HF antenna. and how? is this a good solution to get on the air. i realise that i have limited reach of the "ntenna"

the coax can i strech from my house down a drain that is going under the ground and road to the guardrail and connect it.
 

LtDoc

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Lots of "if's" in that, and they would all boil down to it not being a good antenna on any particular band, sort of. I think it's possible to make it 'work', but that says nothing about how well, or if it would be worth the trouble. Then, you get to wonder about people/things in contact with that guard rail. :)
- 'Doc
 

n9mxq

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Guard rails are usually grounded.. I don't think it would offer much. But hey, dang nice idea...
 

mmckenna

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beverage antennas are grounded...

Another issue you may find is that the guardrail is made up of many sections. Since the guardrails are usually galvanized, you may run into issues where each section of guardrail connects. Actually, it likely may be a pretty lousy connection between sections that may arc when you key up causing issues with rapidly fluctuating SWR etc.

Would be interesting to try, though.
 

SCPD

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hi.

i have a question to you pepole.
i have little space to setup an HF antenna.

but 10 meters from my house there is a gurad rail that is aprox 100meters+ long. can i use that as a HF antenna. and how? is this a good solution to get on the air. i realise that i have limited reach of the "ntenna"

the coax can i strech from my house down a drain that is going under the ground and road to the guardrail and connect it.
Sure but you'll need a matching transformer to get a broad frequency response. It won't be perfect but it'll work as a longwire.

A couple of caveats:

1. What radio would you be connecting this to? A shortwave portable would get seriously overloaded and likely damage the radio. If you have a shortwave receiver, such as an Icom R75 then you'll be ok. I'd recommend two pieces of coax. One from the rail to the house. Use a SO239 bulkhead adapter and ground this part to a ground rod (or if you happen to have a cold-water pipe nearby that would work.)

The bulkhead adapters come in various lengths: UG-363 Bulkhead

Here's a ground clamp example: http://www.dxengineering.com/Parts....FA-4BB0-A7B9-1EDCD8FCDE17}&PartNo=DXE-CGB-150

2. Check your local city ordnance for any laws about modifying road signs, barriers, etc. It may not be legal in your city/area.

Let us know how it works.
 

K9WG

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Two thoughts.

1. I heard stories back in the 1970s of a local ham running 1000 watts mobile with a generator and pulling up to a local guard rail. (Knowing the individual involved, the story was probably true)

2. I have also heard stories of hams using complex objects (in this case a greenhouse frame) for an antenna. The problem was the corrosion between elements created a diode effect and caused massive harmonics.
 

fineshot1

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hi.

i have a question to you pepole.
i have little space to setup an HF antenna.

but 10 meters from my house there is a gurad rail that is aprox 100meters+ long. can i use that as a HF antenna. and how? is this a good solution to get on the air. i realise that i have limited reach of the "ntenna"

the coax can i strech from my house down a drain that is going under the ground and road to the guardrail and connect it.
You may have better luck loading up a metal rain gutter with a tuner.
 

k9rzz

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I've got this ~500 meter long guard rail near my home that slopes downhill to the southwest, and is just adjacent to a city park. I swear, one of these days, I'm hooking into it!


A lot of people will theorize that it won't work. I say, HOOK IT UP. Then you'll be the expert, not because you've thought about it, but because YOU'VE DONE IT.

Edit: Here's the one I've had my eyes on. Only two miles from home.

 
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WX9EMS

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I loaded up the ceiling grid (drop ceiling) in my apartment and worked 40 Meters to European Russia on 25 watts! Try it, what have you to lose?
 

SCPD

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Two thoughts.

1. I heard stories back in the 1970s of a local ham running 1000 watts mobile with a generator and pulling up to a local guard rail. (Knowing the individual involved, the story was probably true)

2. I have also heard stories of hams using complex objects (in this case a greenhouse frame) for an antenna. The problem was the corrosion between elements created a diode effect and caused massive harmonics.
Valid points ... and yes, I was presuming the OP wasn't planning on 1kW! :D

Also I hope you have a quality power meter!
 

SCPD

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sling shot

hi.

i have a question to you pepole.
i have little space to setup an HF antenna.

but 10 meters from my house there is a gurad rail that is aprox 100meters+ long. can i use that as a HF antenna. and how? is this a good solution to get on the air. i realise that i have limited reach of the "ntenna"

the coax can i strech from my house down a drain that is going under the ground and road to the guardrail and connect it.
To be totally honest, I think you would get better results tying a nut on the end of a 22 ga wire and shooting over the closest tree. Yeah, it would be fun to try, but I don't think it's really not gonna play that well, compared to putting a mag mount on top of some metal on your patio or loading up the gutters or even putting a dipole in the attic. It's simply too low to the ground, for one thing. And it's not too conductive. And it's so many wavelengths long, it's basically going to be an end fed beam, for as much as it would work.

If I had my heart set on loading up a guardrail, I would run a wire across the top of it, and every so many feet, secure the wire electrically to the guardrail using sheet metal screws.
 

Rt169Radio

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How much power are you going to use when transmiting? Wouldn't this be a safety concern for anything or anyone that touches the guardrail whether it works good or not?
 

k9rzz

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C'mon, you gotta use your head on these things. I wouldn't bother loading it up on 10 meters, it's only 2 feet high. Same goes with transmitting with it for just about any band. It's so low, that all your enegery is going to go straight up. Could possibly make a killer listening antenna for 40m and down, though.
 

dave3825

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Lol

Whats your answer going to be when the highway dept shows up at your house asking why there's a wire running from the guardrail to your house?
 

KB7MIB

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Wirelessly posted (Mozilla/5.0 (X11; Linux i686; U; en-US) Gecko/20081217 Vision-Browser/8.1 301x200 LG VN530)

K9RZZ, if it could be sucessfully loaded, it would probably utilize NVIS, or Near Vertical Incident Skywave, which is good for regional coverage out to a few hundred miles radius. NVIS techniques are popular with the military, I understand.
 

roadranger

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You should "curb" the idea.

While your at it, shoot the nuts in agreement with this idea over a tree. Might get some good ground wave propagation.
 
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