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I actually like the Force-12 short hatted verticals dipoles as much as the ground mounted verticals with radials. I used to have a Sigma 5 and a Sigma 40Xk - both excellent. I have even used a switch with tuned stubs to make a 4 square out of 4 half wave sloper dipoles off a metal mast (which makes it a "K1WA Array". I have also had a 4 square of verts on 20 with raised radials. I was able to do this when I lived on 5 acres in Lafayette.

Now I live on .3 acres with about a 50 by 10 foot area to play with. I just snagged a used Array Solutions 40M 2 vert controller, which uses a Lewallen / Lahlum curcuit and doesn't dump power like the PVS-2 will. However, I chose the DXE verts because I can simply take off the cap hats and turn the 40M antennas into 30M verts. I ordered a PVS-2 for 30M - so in less than an hour I can go from a 40M 2 element vert array to one on 30M.

All of these arrays give about 4 db gain, and when done correctly, 20 db F/B - so they are like having a minibeam - like the F-12 C3SS or so.

They're all good!

I want to phase 2 verticals, and have 2 DX Engineering 24' hatted verticals. Each have 64 buried radials with the
radials connected using a bus wire.

The have ordered a Comtek PVS-2 which uses a hybrid circuit to let me go end fire or broadside. But it will be 3
weeks before I can get this box. In the mean time - I would like to try to do something else, and also just experiment.

I have built a really nice voltage feed box for my old Bobtail Curtain - it uses very high quality variable L and C
components from Palstar and Ten Tec. I also have a really excellent 8 position switch from DX Engineering - with excellent
port isolation, and the ability to switch grounds and keep them independent and also ground any unused ports. I can also
add a small diode matrix to switch in A, B and A+B. I also have quite a bit of new high quality 50 and 75 ohm coax, and I
am spacing these verts at 35' (1/4 wl).

Anyway, what would you suggest I try with all of the goodies that I have on hand. I'm looking at the various current
forcing feed systems published in the ON4UN book, and also looking at the Gerhke networks.

I also have W7EL's simpfeed program and I have the Palstar antenna analyzer. It lets me measure pretty much everything -
including phasing stubs. I like W7EL's article on "The Simplest Phased Arrays - That Work". Roy describes how to measure
delay lines and antenna impedance so you can cut delay lines that work. There are no components or circuits (per se)
specified in this article.

What would you recommend? I actually think that since my array is broadsided toward the east and west that that is the
direction I will use most. It might even be a bit NW - SE. The N and S endfire directions are not great directions for
the DX I need, so - lots of ideas and questions in my mind, and could use a little "push" in the right direction.

Thanks and 73,

Rich
KY6R

[W6OP]

To just experiment you can just use a T connector. Of course the feed impedance will be low so you want to use two pieces of 75 ohm coax electrically quarter wave long as impedance transformers. Connect them to each antenna and then the T connector to your feed line. You can then, on one side of the T add your phasing line between one 75 ohm piece and the antenna. The ARRL handbook shows the different patterns for different length phasing lines. Basically, 90 degrees (quarter wave) for an end fire cardiod, although 135 degrees is higher gain for a similar pattern. 180 degrees will give you a bidirectional end fire. Since both antenna will have a slightly different impedance you won't get the results you would with a phasing setup like the Comtek.
The key to phasing is to get the power distribution equal between the two antennas. K7NM wrote a nice book about a capacitive match phasing system he calls the C-Match. It works by having the antennas electrically long and tuning out the inductive reactance with variable capacitors so it may not work with your antennas since they are electrically short.
For just experimenting, however the T connector will get you started.

Pete W6OP

[K8TDJ]

Hi Rich, I'd suggest you look up an old Ham Radio article about feeding  two verticals with 450-ohm line and a simple switching network until your box comes and you switch to coax. Simple, cheap, and perhaps, effective. 73, Jim K8TDJ

[KE6VG]

0 degrees will give you a broadsize phase, but not much gain. Are you shooting for Europe/Africa. Did you not have room for endfire in that direction. I am surprised you didn't just put up a half-square using some of those 31' Jackite $50 windsock poles.

Is there any way you could put a temporary light phasing line across the top like a half square or would the top hats mess things up? That way you could just use your matching network you had previously built and voltage feed it.

Rich, I am trying to think outside the "box". I know that is the way you like to build.

I followed the method documented in ON4UN's book to cut two 75 ohm phasing lines - using RG11U. I tuned each vertical and they are withing 1 ohm of each other, and tuned just below 7 mhz. I just have them phased using a "T" right now, so no gain, but I can definately tell the difference on receive.

I also figured out how to use to LC networks with a DX Engineering 8 position switch so I can go broadside and end fire with gain.

I did think about a Bobtail Curtain, half square and even a Bruce Array, but I've been converted to loving burying radials - its an illness for sure.

Anyway, I am so ready for VU7RG now - now I need some luck from the DX Gods. The quality of the DX Engineering switch and verticals and the Palstar antenna analyzer and dummy load made this project a ton of fun.

While waiting for my controller - I decided to try 2 84 degree lines to the verts and a 71 degree delay line (which is described as the Christman method).

I am seeing a solid 10 db front to back - and I am sure that this has to do with the fact that I only calculated and didn't measure the 71 degree line. So I know it is only "almost" phased.

I do expect to get around 20 db F/B with the controller - but its fun to try different methods documented in the ON4UN book.

[KE6VG]

Did you get your PVS-2 yet? I can't decided if I should try one of those. Or, run 3 hatted vertical dipoles like on the Cebik site. Of if I should just stick with a half-square. The half-square works good but only gives two directions. I know you have tried it all. I guess you seem to like the ground mounted better than the vetical dipoles. Did you notice any performance differences... more gain, less noise, more noise, etc. I noticed Force 12 likes using parasitic elements. (reflector/director) But, you don't get as much front to back as phasing.

Spill the beans... let us know all your DX secrets

[KE6VG]

With 60 33ft radials on the ground on 40 meters wouldn't it give you almost 5db better signal than the vertical dipole or full size vertical with two elevated radials? Have you noticed a difference on 40? I think those are the numbers W8JI quotes.

I actually found a used Array Solutions 40M controller, but while I was waiting for it, I used the "Christman method" to feed it with a really superb Dx Engineering 8 position switch (isolation +++).

With the two 84 degree lines to each antenna and a 71 degree delay line - switchable between position A, B and C - where A is S by SE and B is N by NW and C is broadside, I am getting just as good - if not better - performance than with the Array Solutions controller.

I emailed a few antenna guru's who said that when the Christman Method works, it works well and that Al Christman has had some really super ideas in the past. But they said it also doesn't work in every situation. They aknowledged that for most situations, (IF) I were to spend time to tune the Array Solutions setup that it would also do very well.

I am pretty much getting the figures that Array Solutions publishes with the Christman Method - its like having a mini beam with even better FB, and it really was worth putting together. I love it!