[Elecraft] easy simple portable antennas?

[George, W5YR]

Vic, I think that you just wrote an apt description of the famous ISO-TRON
antenna, though it is much smaller and far less efficient that your
industrial-strength version would be. Replace the "dipole elements" with
flat  horizontal plates and the big tubing coil with a conventional-size
coil and there you are: a heavily loaded vertical dipole equivalent.

But, anyway you go, you trade off efficiency for that reduction in size and
are rewarded with a reduction in SWR bandwidth as well.

The EH antenna has been pretty well debunked re the inventor's "theory of
operation" although like anything that will accept r-f power, the things do
radiate what they don't convert into heat. I think that the proponents are
including the heat conversion as output in their "efficiency" calculations.
Perhaps there are niche applications where the form factor, etc. would be a
plus.

73/72/oo, George W5YR - the Yellow Rose of Texas         
Fairview, TX 30 mi NE of Dallas in Collin county EM13qe   
Amateur Radio W5YR, in the 56th year and it just keeps getting better!
QRP-L 1373 NETXQRP 6 SOC 262 COG 8 FPQRP 404 TEN-X 11771 I-LINK 11735
Icom IC-756PRO #02121  Kachina 505 DSP  #91900556  Icom IC-765 #02437


Vic Rosenthal wrote:
 I think that a reasonably efficient antenna could be
> made for 20 meters or higher, if the coil were made out of copper tubing and
> properly joined to the dipole elements.  Perhaps a 6-foot long antenna with a
> coil of 1/4" tubing (in the middle, not at one end) would be practical.  Of
> course I would expect the bandwidth to be quite narrow as well.