The pole at the end of my garden has just up until now been supporting one end of my HF doublet, and more recently had the Wellbrook receive loop on top of it. The Wellbrook loop doesn't need much height in reality. At my previous QTH it was mounted less than three metres from the ground and worked well especially on the lower bands. It didn't seem to work much better in its new home at around 7 metres up on the pole.
So I have had a change around. I dropped the pole down on the weekend. I will find a new home for the Wellbrook, in the meantime I have put a vertical antenna on the pole. What antenna? An Antron 99. Yes its a CB antenna but at the radio rally I attended the other week I picked up "Practical Wireless's" book "Even more out of thin air". This book mentions the fact that the Antron is usable on 18,21 and 24 Mhz as well as we would expect 28mhz. I decided to purchase one and give it a try, being of glassfibre construction it is lightweight and hopefully will not put too much strain on my unguyed pole!
The antenna is 5.6 metres long, has no radials and comes pre tuned to the lower end of 27Mhz. Since at the very least I wanted to use the antenna on 10 metres I adjusted the "tuning rings" at the base of the antenna, hoping to raise the operating frequency a little. This was still when the antenna was on the ground so the adjustment was guesswork!
As it turned out I guessed fairly well. Once up in the air the antenna covered 28 to 29.6 Mhz with an acceptable SWR reading. Digging out the CB rig I have in the shack the SWR on 27 mhz was still within acceptable limits (below 1.5:1) so this is a pretty wideband antenna.
The surprising thing is the Antron covered 24, and 18 mhz without an ATU.
The Western HF-10 wire doublet I use gives me pretty good results but I never really heard much on 24Mhz (12metres) with it. The vertical seems more lively on this band as well as 21 Mhz. In fact I worked LU8EEM on my first call with it.
My very quick evaluation of the antenna so far is as follows:
28Mhz- works well but as far as signals heard to date goes is about equal to the HF wire, sometimes slightly down.
24Mhz- Much more lively than wire- signals generally two three or more s points better.
21Mhz- Generally again signals several S points greater than the wire.
18Mhz- Two or three S points weaker than signals on the wire.
14Mhz- Antenna tunmes using internal ATU but pretty deaf on this band.
It will be interesting to compare this antenna with the Hygain AV12 Vertical when I get that erected. However the AV12 covers only 20,15 and 10.
Here it is up in the air, the visual impact is pretty low I think and I haven't had any adverse comments from my (very tolerant) neighbours.