Antenna Reflecting

[Pamm r]

This may be a silly question but If a 102" whip was mounted in the bed of a pickup truck. Would it matter if there is a rubber mat covering the pickup bed floor? I have always heard signal bounces off metal so would it do better with mat removed?

 

[undertaker]

Will not make a difference. My 102 is mounted on my tool box. And I have the spray in bed liner. I have no issues....

 

[Captain Kilowatt]

To answer your question with a question ...........does insulated wire work as an antenna? Of course it does. Rubber and pretty much any insulator is invisible to RF. Fiberglass antennas have a wire imbedded in the fiberglass and it has no ill effects. BTW the RF does not really bounce off the metal body of the truck.

 

[Road Squawker]

... BTW the RF does not really bounce off the metal body of the truck.

OMG!!!!!

 

[Captain Kilowatt]

OMG!!!!!

Yeah I misstated what I meant to say. I meant to say it does not simply bounce off the metal.A truck body essentially forms a counterpoise for the antenna if it is less than a minimum of 1/4 wave in all directions under the antenna. It's function is to return RF currents back to the feedpoint. Yes RF will reflect off metal however. In an antenna with a very large groundplane the effect is to "pull" the RF lower to the ground giving a lower take off angle by lowering the incident wave and thus lowering the reflected wave.

 

[DainBramage]

Yeah, thats why many commercial AM BC towers have all those junk cars parked below the antenna.

Any metal will work but, junk cars are cheap and the "park" well.

 

[Tallman]

Yeah, thats why many commercial AM BC towers have all those junk cars parked below the antenna.

Any metal will work but, junk cars are cheap and the "park" well.

Really? Where do they do this?

 

[Tallman]

This may be a silly question but If a 102" whip was mounted in the bed of a pickup truck. Would it matter if there is a rubber mat covering the pickup bed floor? I have always heard signal bounces off metal so would it do better with mat removed?

As long as the ground is properly made it will have no effect.

 

[Paul-W5lz]

I think everything has been covered but just in case. That bed cover isn't doing anything significant dealing with RF. You do have to make sure that an antenna is mounted to the metal, but after than it's usually going to work fine.

 

[Onelasttime]

Yes idea's like RF ground vs electrical ground and "ground plane" are rather abstract idea's to most and seldom understood rightly! Kind of like how "blood thinners" have nothing to do with viscosity of your blood and are named poorly compared tot heir true function!

 

[loosecannon]

Yeah, thats why many commercial AM BC towers have all those junk cars parked below the antenna.

Any metal will work but, junk cars are cheap and the "park" well.

They work even better if you fill them with salt.
LC

 

[Paul-W5lz]

That's sort of like carrying a bucket of dirt in a car for grounding... ain't it?

 

[Road Squawker]

...