For many people without building experience following instructions
on how to make something is not always that easy. Many manuals and how-to
sites can be hard to follow, not well explained, and simply assume too
much. I  hope
to take you step by step through the process of building a magnetic loop
out of copper pipe. I will list all the parts you need, where to get them,
and how to put them together. If I can do it, I am pretty sure you'll be
able to do it too! Just try not to get intimidated when I use words like
torch or solder. I will explain that as well as I can.. So read through
the article. Re-read it, and then go out and buy your parts and tools.
And if you follow the steps, you should have yourself a nice loop antenna
that works well and fits at almost any QTH.
Let's build a loop for 20 meters that exhibits around 65% efficiency. We'll make it out of .5 inch copper pipe and each side will be 3.5 feet long. This loop is nice because is it so light and easy to place pretty much anywhere. Yes, I most certainly could and will give you other designs that are more efficient, but I want to start with something easy to make and use. Once you get the hang of it, you will be able to move on to more challenging projects. We'll do it easy and use a coaxial stub as a capacitor for each band and I'll show you how to change bands when you so desire. Alternative Design: I would also recommend a loop that is 30 inches on each side and made from one inch diameter pipe. It won't be as efficient as the 3.5 foot version, but it will be close to it in performance. What I like about the 30 inch version is it fits in car trunks very easily. It will also store well in a suitcase. It is more portable than the 3.5 foot version and more sturdy. DISCLAIMER: I take no responsibility if you end
up getting hurt or damaged in the process of building this loop. Sorry
guys, but considering the litigious nature of people these days I have
to say this clearly. You're on your own with this one. You hurt yourself,
or damage your own property, it's your problem. If you have any doubt about
your ability to build this loop, or follow these instructions without getting
hurt, DON'T BUILD IT. Even if you think you can build this loop and not
get hurt and do get hurt, your doing it at your own risk! This information
is purely for your intellectual pleasure and if you want to go ahead and
build it, that's your choice and your responsibility. Having said that.
let's get down to details.
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