Been a busy few weeks which is why I've not posted much here.
First, we had a bit of an accident.... my older boy ran over my VHF/UHF coax feed with a lawnmower. Expensive ouch. So I'm waiting to get the coax replaced for the short stuff. More on that in another post.
As some of you will know, I started a new job just recently and as a consequence of that, I'm now driving a new rig. Been having some problems with getting an antenna to work on the thing. If anyone has experience installing VHF/UHF antennas on a Volvo, drop me a line, please. I'll post more on that in another post as well.
The good news on the home front, and the subject of this post is the new VG4 antenna I have waiting to go up.
It showed up several days early.
It's a multi-band trapper, some 25-26ft tall (just about the same height at my IMAX2000, and it is resonant on 40,20,15 and 10m.... though many reports suggest it's quite good on 6m as well... and the other bands in between it's stated coverages... 30m17, and 12 can be turned with just about any tuner.
Cool beans!
The attraction for me was the lack of ground radials needed, since the whole thing is elevated. Being elevated, it will have a performance advantage over ground-mounted verticals with buried radials, amounting to about 4db or so, vs a 1/4 wave vertical on a given band. (Rudy, N6LF gets into this aspect of the general performance of elevated vs buried radials Here, if you're interested. (PDF)
I'm hoping that it's top loaded design will allow it to perform within shooting distance of the IMAX2000 I currently use. As most of you know, that's a tall order.... the IMAX is tough to beat on the short end of HF. Being top-loaded, the VG4 will not suffer from lower elevation on the shorter bands, such as 10m for example. (I'm still running the ROC City 10m net these days, and obviously want the best signal I can get for that band. )
On the other hand, since the IMAX only works well on 15-10m without the external tuner... And down to 20m and up to 6m with it, with some serious signal losses below 15m for efficiency reasons, it's a little constricting. I've been really looking forward to getting live on 40 again and to better signal on 20, so, this may end up being a hard choice.
I may end up setting up both verticals if the top-loaded VG4 doesn't perform as well as the collinear design of the IMAX.
If, on the other hand they're fairly close, I may end up taking the IMAX down. That thing is a signal monster and I'll hate to lose it. We'll see. Because of some space and hardware limits I'm dealing with, I'll have to take the IMAX down anyway, at least initially.
I gatherthe VG4 is going to be a handful to put up, and get tuned. Tuning it will require a number of ups and downs, and that doesn't appear to be a one man job. Have a look at the dimensions to see why. It weighs around 15lbs, too, and that's without the weight of the mast and the coax and so on.
As for tuning it, I've seen reports that only a couple of cm adjustment per band, give around a 500kc shift in center tuning on 40, with the remaining bands being somewhat more forgiving. The Q on 40m is a bit high, as you might expect from a trapper of only 26 feet or so.
Once up however, it looks like it'll be pretty much bullet- proof. the Radio Oddity site suggests:
The VG4 is rated for high wind environments. After a normal installation, it can resist a category one hurricane with no guying required.I do have high hopes for this stick. we'll see if that mans out over the next couple weeks.
Of course I'll be posting results here.
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