The Ham Radio Live YouTube channel recently had a very interesting interview with William Des Jardines, W1ZY about a Phased Array Vertical Antenna as well as a simple Beverage Antenna. A video of the talk is embedded further down.
I think anyone who is interested in making and experimenting with antennas will find this of interest.
The presentation is a bit light on graphics so let's address that first.
The image above shows the view from above of the radiation pattern. Signals coming from the right are added and there is a small gain of about 3dB. The signals from the left are out of phase and there is a large drop in this direction.
With a relay and suitable phasing lines, the direction of the array can be flipped to the right or left at the flick of a switch. This has obvious advantages for say propagation and antenna tests as opposed to waiting for a Yagi to turn on a mast.
The talk also covers Beverage antennas which are used for receive only, especially on the lower HF bands.
The video is shown below and the part of interest starts at 11:30...
There are a two links for more information.
W1ZY has an article on his substack site HERE
W1ZY's QRZ page also has a LOT of information, see HERE
6 comments:
Phased verticals are great, and fairly simple, and not so bad on space uptake.
But if I lived at a shore as in the image, the water would be giving, typically, about 10dB free gain from just one antenna, and would also be directional towards the water.
I doubt personally that it would be generally worth the added effort of having a phased system in that environment. Nothing wrong with it, just another way to think of what's going on, especially as many have never worked at the water's edge.
To Photon / MW1CFN: I think the big advantage with the phased verticals is not so much the forward gain but the rejection off the back.
A good example might be say someone on the west coast of Wales in an ARRL contest. They may want to work only North America but really want to reduce the signals from Europe.
It's also really good to be able to flick a switch and beam in the opposite direction. For example, if you're hearing Australia, is it short path or long path? Flick a switch and see the difference.
Thank you!
Hello,
5-6 years ago I was almost daily on 40 m and had a number of qsos with W1ZY.
I can tell you - all he has written is worth attention! Exactly what John said, toggling the switch will help you understand both - understand the propagation path or reduce unwanted qrm. Gain of 3 dB might sound not significant, but try dipole against 2 element yagi (even moxon type) and I bet you will change your mind. Sometimes it's of major importance to skip the noise floor at your RX/QTH and can make difference.
W1ZY - RESPECT!
I apologize, forgot to sign previous post.
It was me, Gogo 9A6C
(in 'Allo 'Allo English, hi)
Thank you, Gogo.
BILL W1ZY
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