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A 1/4 WAVE VERTICAL FOR 10 METRES
ALSO COVERING CB

This is a dead simple aerial which really does work wonders. It's an eight-foot length of 15mm copper pipe sticking out of a hole in one of the roof tiles of my house. And there are four lengths of wire inside the loft acting as radials. It's fed with 50 ohm coax, and an ATU is not necessary. The total cost of the aerial? Next to nothing. How well does it work? Bloody well. From my QTH on the south coast of the UK I've worked many 10FM repeaters in Europe as well as several USA repeaters. Plus, many simplex contacts in and outside Europe with excellent reports.

I used to have a 5/8 wave CB aerial for ten metres, but my copper pipe quarter wave is far better. This is due to several reasons. The copper pipe is about thirty-feet high and the 5/8 CB aerial was only up at ten feet - yeah, fair comment. But the copper pipe has radials and the 5/8 wave CB aerial had none - this is a major factor. Add to that the crappy and very lossy matching circuit built into the base of the CB aerial, and my copper pipe wins hands down. Also, the eight foot copper pipe aerial is far less obtrusive than twenty something feet of very poor quality aluminium held together with jubilee clips.

This copper pipe aerial came into being by chance. I stuck the eight-foot length of pipe out of the roof of the house to support the horizontal section of my inverted L. It then occurred to me, in an hour of madness, that I could load the pipe on ten metres if I added four radials. The radial wires come down at 45 degrees inside the loft and were simple to trim to get the SWR down to 1:1 So, I have a supporting pole for my inverted L which doubles up as a great ten metre aerial.

 

10 METRE 1/4 VERTICALHere is the diagram of the aerial with its radials. You don't have to use a copper pipe as the vertical section. A fibreglass whip or even an eight foot length of wire taped to a bamboo cane will work well.

I used so-called bell wire for the radials, but any old wire will do. If it's free, then use it. Don't buy copper pipe - rip a length out of your bathroom or kitchen. Don't spend money on aerials when you could spend it on booze!

 

 

 

 

TEN METRE QUARTERWAVE AERIALThis is a view from outside. The thin wire you can see is the horizontal section of my inverted L supported by the copper pipe. I can say, in all dishonestly, that this aerial out performs any 5/8 wave CB aerial which doesn't have radials - at any height.

 

 

 

 

 

 

 

 

 

 

BASE OF THE AERIALThis is a view from inside the loft. What a lash up! The four white wires are the radials, which were pinned to the roof rafters but seem to have come adrift. Oh well, it still works. You can see the 50 ohm coax coming down from the mess. The outer braid goes to the four radials and the inner to the copper tube.

The white plastic 15mm pipe coupler insulates the aerial pipe from the copper pipe below, which is resting on a wooden beam. Again, like all my projects, it's only temporary. I'll be tidying it up soon, I promise.

Seriously, you can see how simple this aerial is. My lash up doesn't look pretty, but it works damned well. I've had to tear the roofing felt away to get to the tile, but what the hell?

The huge croc clip connects the inner of the coax to the aerial pipe. One day, I'll solder it and do the job properly. One day soon? Yeah, right!

 

Making the hole in the roof tile was fairly straight forward. Of course, it depends on the type of tiles you have at your QTH. Slate might shatter, so be careful. I found that I could slide the tile out from inside the loft, which made life easier. I have a few spare tiles at the end of the garden but, luckily, I didn't need them. I made the hole next to a roof rafter. This will allow me to clamp the base of the copper pipe to the rafter - one day! I then sealed around the hole with silicone bathroom sealer.

DISCLAIMER

If your roof caves in - don't blame me.