Possibilities with loop on 160

[WA2ROC]

I was in a QSO with several folks last evening, Todd KAQ among others, and I posed the question of using my 300 foot 80 meter loop on 160 somehow.

I am feeding the loop now with 450 ohm open wire and tuning it with a Heath 2040 tuner.  This will shortly be replaced with a Tucker T-3000, aka Vectronics HFT1500.  I will be using only my  Viking  II to supply about 100 watts resting carrier and maybe 350 watts on voice peaks, so arcing and flashovers shouldn't be a problem, I hope.

One possibility would be put a large knife switch half way around the loop, open it up on 160 and use it as a half wave circular dipole.

Another suggestion was removing one wire on the open wire and feeding it as a circular long wire.  I probably would need some ground radials for this option and there would be lethal voltages at the open end of the feed line, so I am shying away from this one.

Maybe tying both wires on the feedline together end feeding it as a circular long wire???

Or maybe just trying to load it up like a really short 160 meter loop???

I don't need to work DX, only locals and East Coasters or whoever hears me.  Just want to get on 160 and join in the fun.

Tnx and y'all have a good day.

[K5UJ]

I had a horizontal loop (is yours horizontal?  how high up is it?) about 1 wave at 4 MHz and up 30 feet +- 5 feet.  fed with ladder line (not window line) in the middle of one side.  I toyed with the idea of using it on 160.  I considered everything you have mentioned.   Every possibility had some sort of problem--lack of ground system, opening the far end to make a circular dipole (voltage arcs across the switch or relay) but after I came up with solutions, there was no getting around one thing:  I'd have a crappy antenna.  Think about it:  Would you use a loop half the size of what you have at half the height on 75 meters?   Well, that's what you'll have on 160.   I threw in the towel and put up an inverted L for 160.

Rob

[Ed/KB1HYS]

Break the middle of the loop opposite the feed line. Insert a shorted stub of feedline 1/4 WL long on 160 freq of interest.  It'll be a 1/2 wave on 80, so the antenna will function as a dipole (more or less) on 160, and a loop on 80 because of the impedance transformation (a 1/4 WL shorted stub is an open and a 1/2 wave stub appears as a short).  Bandwidth will narrow down a bit (no free lunch) but if your using open wire and have a robust tunner shouldn't be a problem.  Simple and low maintenance.

[WA2ROC]

Ya know, I have the extra wire available, and the loop now is located in part of "common area" behind the house.  There's a lot more trees back there, so I could just add more wire to the existing loop, even though it may head out is several weird directions.

But I would have a "real" 160 meter loop that could be used on the lower bands too.

Yes, it is horizontal, and maybe 40 feet in the air.  Maybe not optimum, but it's what I have and it seems to do OK.

When the leaves fall from the trees, out comes the ladder.....

[W4AAB]

Just checked out the Loop Skywire by W0MHS. The one in the Wire Classic book has a 272' loop at 40 feet above ground. For 160m, that would need to be at 80 feet, however, I know someone who is using a 546' loop at 55 feet, and it works great. Do what you can with what you have available, and good luck!!

[ke7trp]

If you had a big balanced tuner, You could probably just load it up and go.  You could feed it as a long wire which is probably your best bet.  Hook both ladder line legs together to the long wire output of your tuner. Make sure to hook up the jumper if your tuner requires one.

You will need a good ground to the tuner.  I did this with my 80 meter Doublet.  I have a good RF ground here with 9 full size ground rods in Copper sulfate with a couple of hundred ft of wire out under the antenna.

I stopped playing around with this when I discovered the simple inverted L for 160. It booms and its coax fed. Only drawback is that it is narrow.

C

[WQ9E]

How high is your loop?  You can tie the open wire feeders together where it goes horizontal and feed it as a top loaded T.  A ground system is valuable in this configuration.

[WA1GFZ]

I was thinking of running a wire across the ends of my Vee and doing the same thing. I simulated it with a break in the middle and found it becomes a good high angle antenna with everything mostly above 45 degrees. A good looking local antenna configuration.

[KM1H]

For that stub the Q is the killer for QSY bandwidth so consider some galvanized fence wire....its cheap enough to experiment.