I have a decent-sized but not huge yard (roughly 50x100' / 15x30m) and I'd like to get on the 160-metre band. It's hard enough to get out on this band so I'm looking to do something reasonably efficient. Bonus if it can do well on 80m too.

I realize there will be some subjectivity to the results but I'd like some suggestions as to what the practical alternatives might be.

Right now I'm thinking some sort of a vertical antenna ought to do fine (adequately long radials will be a problem though), and we have an easement behind our yard where I could run a Beverage-like wire antenna quite a long distance, along the fences. I'd have to be discreet about it but none of the fences open to the easement (it's like an alley but grassy and not used), so it might be an option if it will help me on receive.

Am I on the right track? A simple 160m dipole would be perfect but there simply isn't space.

Almost any 160 meter antenna is a compromise. With limited space or budget, the compromise tends to be larger.

At first glance, a dipole that is shortened by loading coils might appear quite attractive. With well designed coils, the efficiency of a shortened dipole can be relatively good and the gain can be within a few dB of a full length dipole. But unless the dipole can be hung very high (> 40 meters and optimally 80 meters), the directivity of the antenna will be largely vertical making it more effective for local communications (NVIS).

Vertical antennas facilitate longer paths but they require a good ground system in order to improve their efficiency, especially with a shortened vertical element (< 40 meters). Many hams have success with an inverted L arrangement. A starting length of 40 meters of wire is common with as much vertical as possible and the balance of the wire running horizontally from the top of the vertical piece. This horizontal component is viewed as a capacitance hat.

It sounds like your situation will not allow elevated ground plane wires. As a result, run as many wires in all directions for as long as you possibly can and keep them very near the surface. Consider leaving them on the lawn secured with lawn staples so they sink into the thatch. The highest current in the ground wires will be near the vertical so more wires are generally better up to perhaps 60 or so wires depending upon your ground conditions. More wires has no downside other than additional cost and effort.

In order to minimize losses in the feedline, use a remote tuner at the base of the antenna. You may need to supplement the tuner with a large conductor base loading coil. Unless you are running high power, you can then run RG8X back to your shack with virtually no feedline losses.

The ability of the antenna to work on other bands will depend upon your final chosen geometry. You can model multiband performance with a NEC based program.

  • Thanks. We have very good ground conductivity here. I hope that translates to good grounding conditions for these purposes. It's dry here at times. Your idea of letting the thatch take over the ground wires is a good one. – Jim MacKenzie VE5EV May 14 at 22:01
  • Great answer and good suggestion about the Inverted-L. Many Topbanders have found that K2AV's folded counterpoise desgn is a fairly decent substitute for a good radial system for it. (I just used two elevated 1/4 wave radials about 10' high under mine.) – Mike Waters May 15 at 18:13

I've read about DDRR antennas as well. Here's an article about a 40m version: http://www.w1npp.org/events/2010/2010-F~1/ANTENNAS/LIMITED/711202~1.PDF A quick Google search will likely return a 160m version or one that can be easily scaled.

Personally, I remain skeptical and have never built one, and my Elmer called them his "mole suppressors." YMMV.

  • The DDRR antenna is very inefficient, and that old QST article didn't point that out. The DDRR antenna was based on the misplaced notion that displacement currents from the ring to the groundplane would radiate. – Mike Waters May 15 at 16:38

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