PVC 800 mhz scanner antenna

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bms

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Jan 11, 2002
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Maryland
Hi:

I would like to make a cheap covert scanner antenna for outside the house. The counties are mostly 800s but I also want to listen to railroad, some marine and other VHF frequencies. Right now, I have indoor rubber ducks on my TRX-1 radios.

What do you think of a ½ PVC pipe with a wire inside?
What is better, PVC or CPVC?
What about schedule 40?
Should I have one wire from the center conductor or does it have to be a dipole?
How long should the wire(s) be?
Am I correct it doesn’t need a ground if it’s a dipole?
Do I need lightning protection if it is not higher than the peak of the house?
Can the PVC and wire be painted to match the house?
Can I use 50 feet of coax or ladder line?
Can I use one antenna for two radios?
There are very tall trees in my neighborhood. Can the antenna be near the peak of the house or does it have to be higher considering the next to further distance one system is 22 air miles to the antenna amd about 30 miles to the furthest?
Thanks.

BMS
 

teufler

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ST PETERS, MISSOURI
First a wire in a pvc pipe works fine. The pvc is non conductive. pointing, as long as its non conductive paint, non metal base, it will work. A vertical dipole design. Attach coax to the center of your dipole and have a separate leg for 800, and say 155. 800 would be .55 feet for the dipole, and 3.02 feet for vhf.
KWARC Dipole Calculator calculator. Actually any vertical antenna would be better than an inside rubber duck.
 

SteveC0625

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Oct 24, 2009
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Northville, NY (Fulton County)
If you are going to place the antenna wire inside the pipe, use Schedule 20 PVC. It's much thinner and therefore lighter weight. Take a look at Ed Fong's J-Poles on Ebay for some good ideas about building your own. I have a pair of them and they work very well for receive. Up until now I've done minimal transmitting with them, but they work fine for that, too.

If you plan to build a mast out of PVC, use Schedule 40 for that section.

Use coax between the antenna and the radio. There's tons of info here in previous threads about that.

You can paint the coax to match the house, but there are conflicting reports about painting the antenna itself. Do some research on that. I would not paint it.

You should always use lightning protection. A simple inline protector is adequate provided you ground it properly. Take a look at the coax installation for cable or satellite tv. It's simple and not expensive. I have two on my house, and they are both directly grounded to a long grounding rod buried in the ground outside the foundation.

For receive only, you would need a simple splitter for the antenna feed into the radios.

If covert is important to you, take a look at the ventenna.com website. You can get a lot of great ideas for a DIY from that alone. Or maybe just buy one of their products.
 
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