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In another QA here, there's a picture of an antenna I identified as a "discone": What are these antennas used for?

One commenter noticed that antenna was actually a "Discone, but no disc, just the cone..." so I gave it a second look:

View of antenna in question near Heidmoosstrasse

Sure enough, no "disc". But now I don't even see "the cone" either!

There seem to be two things going on around this mast:

  • Wires going from the mast to the ground. I count two sets of four such wires. These wires have a number of "bumps" on them. Probably guy wires to support the tower; with the bumps being insulators which split them up electrically so they don't mess with the pattern as much?
  • Some eight or ten wires all around, running from the top of the mast, passing over a hoop halfway down the mast, and then gathering again at the bottom of the mast. These must be the active elements?

Unlike a discone, which is derived from a biconical antenna where two cones meet at their point, this antenna seems to be shaped more like a geometric bicone where two cones are joined base-to-base instead.

What type of antenna — or, antenna array — is this?

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  • $\begingroup$ en.m.wikipedia.org/wiki/Discone_antenna $\endgroup$ – Mike Waters Sep 23 at 20:01
  • $\begingroup$ After I wrote this question, I noticed more details about the antenna shape but was still stuck on my "discone" impression. As a result the question ended up a muddled mess. I've now ± completely reworded this question to ask about the actual antenna arrangement pictured. $\endgroup$ – natevw - AF7TB Sep 23 at 23:59
  • $\begingroup$ Lozenge has more than one definition in the dictionary. You mean "diamond shaped", but by far the most common is throat lozenge, a medicine. I suggest you change lozenge to diamond to clarify the meaning. $\endgroup$ – Mike Waters Sep 24 at 17:18
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This is probably a conical monopole antenna, as described by E.W. Pappenfus, WB6LOH, in QST for November 1966. Antennas of the size order shown in the OP are probably for use from 4MHz and higher in the medium-wave band.

Paul Lee, N6PL, describes the "discage" in, "The Amateur Radio Vertical Antenna Handbook" , which could explain the "disk" one may observe atop such antennas. The top disk is fed separately against the wire cage to provide improved coverage of the shortwave frequencies.

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  • $\begingroup$ Thanks, I'm seeing some variation within "conical monopole" designs but I think that must be the correct term. I found flickr.com/photos/ssave/6947932920 where the poster elaborates: "a conical monopole is a 'fat' monopole which increases the bandwidth of frequencies that can be used with the antenna." $\endgroup$ – natevw - AF7TB Sep 24 at 16:49

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