Adventures in Antennas (The Random Wire)

Adventures with Antennas

The Random wire

From my previous post, I was experimenting in a random wire antenna. The first thing I needed was a 9:1 UnUn to get the antenna impedances to a range the autotuner can handle. I followed the blog entry Magnetic Longwire Balun which worked out very well. 

The main ingredient was 10.6Mtrs of wire,a 6M telescoping fiberglass pole and some bungee straps to fix the pole to the fence-post.

Right next to the antenna is a metal fence, which I dont like! so I opted to elevate the base of the antenna to the top of the fence post. It was convenient as the counterpoise was the actual fence. 

You will notice that the black pole is leaning forward as I wanted the the last 4 meters to be a pseudo-V shape.

The antenna analyser shows that the antenna being quite poor in the frequencies I want to use; which is good.

Surprisingly it show that it will work okay from 18Mhz.. well barely!

The performance

Connecting to the LDG Z-11 Pro tuner, it had no problem of reducing the SWR to 1.5 and below. 

Firing up WSPR and running the radio at a massive 2 watts - I was impressed with the spots; considering it was made in 10 minutes at my dismal skill level.

The random wire will not win any awesome propagation awards, but as a compromise antenna it does the trick.

Adventures with Antennas - Dipole [Previous]

Adventures with Antennas (the Dipole)

Adventures with Antennas (the Dipole)

(playing with wires)

As all the HF radio equipment I use is QRP, I tinkered with the usual inverted V configuration. Mine is constructed using scaffolding poles, aluminum sections and lots of concrete with a pivot base. Just cos it pivots, doesn't mean it is easy to lower and raise. 

There are 2 antennas in the picture, the inverted V is the silver one. The apex is 10mtrs and it has a 20M and 40M HF dipole elements attached.

Its pretty much tuned for the 2 bands I want to use, but the LDG Z-11 Pro autotuner I use will make a match of a wet piece of string. 

The other antenna shown is a random wire experiment as it was the first time I have ventured in to the world of the UnUn.

But first, the Dipole; from the antenna analyser, its tuned for the frequencies I want. -perfect-

showing the HF spectrum from the analyser, the two resonant frequencies where tbe impedance is 50ohms or there about is shown.

Watch out for 2E0GRU on the Airwaves.

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