Underground Antenna Experiments on 160 meters.

Some years back I buried a 30 metre (60-feet) auminium wire one spade
depth in my back garden. Wire was 1.5 mm in diameter. Soil
resistivity about 100 ohm-metres. To scientists that's 10
milli-Siemens. The near end of the wire came up in the shack. That's
under my kitchen sink. It's still there. Open-circuit at the far end.

As a counterpoise, something essential to tune it against, I erected a
wire in the form of an inverted-L. This was about 30 feet high and
overall length about 140 feet. I chose this length because it fitted
nicely into my back garden. The front garden is too short even for an
underground antenna.

On the 160m band I fed into it about 30 watts from a home-brew
transceiver so I can't provide for the record a manufacturer's type
and serial number. However I still have the transceiver which can be

Despite a high local noise level of S-6 I was able to communicate up
to 60 miles with mobile stations in broad daylight on SSB. After
sunset I could easily communicate with most of Europe on CW.

I think a record of these buried antenna experiments should be kept
for posterity, alongside the famous biblical work of B,L & E.

By the way, as you see, I did remember to measure soil resistivity. It
was the first thing I did. What buried wire do you think I used to
measure it?
Reg, G4FGQ


Relevant Pages

  • Re: Using a copper water pipe in place of a ground rod?
    ... a pump - this hydraulically drills the pipe into the soil... ... this creates a large area of metal in contact with the soil.. ... bare wire slit into the soil, run heavy gauge wire from the stake just ... The coax shields are grounded at the top and bottom of the tower ...
  • Re: Heating Elements for the soil
    ... an electrical heating system, some kind of grid/mesh in the soil. ... Just need to keep the soil around 70 degrees. ... He then poured the slab. ... had brought the 2 ends of the wire out of the slab before he poured ...
  • Re: high earth resistance
    ... So, if you were to integrate over the entire width,or over any region which is symmetric over the wire, the *net* is entirely radial, but if you look at a small region, directly adjacent to the wire, there will be current diverging from the wire as you move outward (assuming current flow is outward... ... Another sort of "hydraulic" model would be if you represented the radials as below grade drainage ditches which have a lot more pitch than the surrounding soil, so the water tends to flow diagonally down the ditch walls. ...
  • Re: Homebrew HV hiZ scope probe
    ... Probe cables, at least modern ones, use foam dielectric, hence lower ... 50 ohm per foot region. ... most hits were Chinese sellers, many do not say how to buy, those that do say how much do not give resistivity of the wire. ...
  • Re: prototype
    ... I can't find constantan in my MWS wire catalog, ... we all know that thermal resistivity follows with electrical... ... to visit and make too much noise. ... I wish there was a copper alloy with more resistivity. ...