I-Pro Home - Pro-Antennas
A quarter wave Vertical with capacity end loading
I had been planning to re-jig the whole set-up here at NKX towers and one of the things I had been looking at was a change in antennas, or at least "An Addition", and was thinking of putting up a vertical such as a Hy-Gain 14 AVQ, or one of the multiband hustlers - I had seen the video clips read the literature on Carls range of Antennas and I have to admit I was sceptical as to their capability to cover the bands 20/17/15/12/10m being a non-resonant type quarter-wave in vertical mode with end capacity loading.
The antenna is app'x 16 feet in length which made me think it would be mainly intended for 20m (Carl does state clearly the antenna must be used with either an internal or external ATU).
I finally decided to take a gamble and duly made the purchase - this antenna is free standing and I have mounted mine in a corner of my garden near trees (Not Ideal) but it IS sheltered - one of the things that appealed to me was there is no need to lay radials out though you could experiment.
First impressions:- Well manufactured using aero alloys, looks strong enough (though the 1" thick main length of the antenna could be 11/4" for added strength) wether this would add significantly to final costings? (Probably)...
Do study the instruction sheet to fully familiarise with what it should end up like, it would be very easy to get the balun assembly up the wrong way (Though it I S clearly marked with a red sticker which should be upper facing) other than that anyone with a modicum of skill with a spanner and screwdriver should master assembly without hitch.
I wont go into assembly here, so assuming you followed the instruction sheet you should now be able to mount it, I have used a clothes pole spike hammered into the ground with a short stub pole to which attaches the clamp and the base of the antenna "Drops In", it's very simple and when not in use you can "Lift it out", and lay on the lawn - Store it in your garage or whatever you will (Quite Handy).
Now you can check it out - I went straight to 20m and switched on my new Ldg AT 200Pro antenna tuner and found difficulty in tuning, in fact ALL the bands were difficult to tune, and to be very honest - the tuner appeared to be making a bit of a meal of it, so I switched to a manual tuner and 20m was again proving difficult to find a sweet spot, though I could get a match on 15 17 and 10m (Encouraging) - I tried another Ldg tuner and it was ok (All Bands) so I finally tried the new tuner on a resonant dipole and it failed to tune properly so I suspected a faulty tuner (Replacement was 100% ) having replaced the Ldg200Pro all was well I saw we had pretty much 1.5:1 or less on all the bands on the Cw ends with a pretty wide flat response across 10m.
I have now made a good few initial contacts using this antenna - it's lively on 20m (Very Lively) in fact I would say 1-2 s points up on a dipole, same for 17m, 15m looks good too I have not worked on 12m yet as conditions have been so poor but did find a Sporadic E opening the other evening up on 10m and worked across EU.
I completely forgot the auto tuner in my rig ;-) My FT450AT tuned it easily on 20m but it's not as fast as the Ldg as it has the memory function.
Couple of points:
If your leaving it erected - Guy it! Bottom and central insulators take a fair old strain (I feel they could be longer and pass further into the main boom with a couple of extra bolts)
Forgot to mention the two end capacity elements - they are 2.5m long.
Also the feedline is supposed to take off at 90 degrees from the antenna - this could prove difficult though I have a nearby tree available for support especially as I have 30m of RG213 feeding it - this too adds to the weight.
As I said earlier, I was unsure about this antenna but thought I'd give it a go anyway and for me this is an experiment, there are those who in the past have knocked antennas of this kind (Transworld Antennas "Adventurer", and the Sigma 5 to name but two) but right from the off this antenna brought 20m to life - It's possible to break it down into two parts with the removal of two of the central bolts for storage, portable use ? probably not ! at 16 feet total length - still playing with this antenna and because of recent poor conditions through the latter part of june have been unable to winkle out any real dx but we're working on it.
Like ALL "Multiband Antennas", they will be a compromise at best - just that some DO happen to work better than others - the centre matching balun assembly is probably an unun device and thus far have no information on it, but as was recently pointed out the likelyhood is that it will be "reactive", and coaxial cable should be terminated in a resistive load, the system losses will depend on the unun's properties and imedance, and the length of coax ?
All that aside, this antenna works well on 20m and pretty well on 17m I have not performed exhaustive on-air tests yet but had an all day session one sunday using Wspr @ 5w and was reported by a string of W's a VE most of EU couple of VK's VU and 4X - what else can I add? Dont bother with 30/40m you'd be better off with a simple dipole, there is (or will be a conversion kit for these bands) .....!
I have found this antenna presents a good match on all the bands 20 - 10m and my New Kenwood TS590's internal tuner matches it as well.
Whilst this may not end up as my main antenna it does work - I reckon it's worth having just for 20m, and the other band capabilities are a bonus - and when your finished with it just lift it out and store it, and to be honest you could break it down it does'nt take long.