Understanding Antennas For The Non-Technical Ham

Here is a TERRIFIC primer on antennas! Most everything a newbie can want to know about different antenna types may be found here! And the author, Jim Abercrombie, N4JA, has made this 74-page PDF available for free!

http://www.ad4dx.com/pdf/basic-antennas.pdf

Section V." THE IONOSPHERE AND MODES OF HF PROPAGATION" is especially good.

This same paper is available for download at Hamuniverse.com, too.

http://www.hamuniverse.com/n4jaantennabook.pdf

I'm pouring over the myriad of commercial and home brew antenna designs for my first HF station so the timing couldn't be more perfect. Thanks for bringing the guide to the board Frank.

This section is VERY INTERESTING but is a lot to take in for the uninitiated. So far, I'm seeing that sunspots can be good or bad depending on the frequency in use, the time of day, and the distance of the receiving station from the transmitting station. I'm going to take a break from it and come back in a few hours to see if my brain cells will allow a deeper understanding to take hold. I'm sure it won't be the last time.

On the other hand, propagation is what it is. You can quickly dial around, see which bands are working, and which ones are not, and you will soon have a feel for it. "OK, it's 14:00 local, 20, 17, and 15 meters should be good to go..."

I made a lot of contacts back when we had no sunspots and the "old timers" were griping about poor propagation. I just went ahead and filled in my log and appreciated what I was able to do.

If you are limited to only one band (say, 20 meters), and only one antenna system, it can be a problem. Many hams can attest that on a long-haul QSO, there will be points in between the stations that simply won't hear the conversation.

Now go study NVIS. That will help you to understand that you can make the sunspots work in your favor ALL the time! (Or at least, when they are present!)

ETA

Consider the 'takeoff angle' from your antenna. If the angle of the main lobe from a tall vertical antenna is, say, 10-15 degrees, your skywave will go nearly to the visible horizon, and far beyond, before it hits the first F1 or F2 layer, whichever is available at the time. On the other hand, if you have a short vertical, your takeoff angle will be closer to 35-45 degrees, or even more (depending on the band you are using), and your skywave will contact the F layers much closer to home.

You can work DX throughout the sunspot cycle on the low bands. A good antenna, a working knowledge of CW, and access to the Extra class sub-bands maximizes your chances of success.

Low Band DXing

Right click, save as. This is going to get printed monday at work


Awesome find OP.

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