20180804 - 80m antennas from the audience

Post date: Aug 4, 2018 1:31:12 AM

Charles Nk8o:

My current primary antenna is an 88’ (26.82m) symmetrical doublet at 44’ or 13.41m per leg. Elevation is 15m above ground level, strung between two trees.  This is fed with window line as far as the entry point to the shack.  A 1:1 balun is used to couple the balanced to unbalanced connection, and of course, an ATU between the radio and the antenna (or in the radio).  I use this antenna on 80 through 6 meters with acceptable results.

Mark VK6BSA:

http://www.iw5edi.com/technical-articles/w5gi-mystery-antenna

Denis VK6AKR

2m and 70cm pogo stick constructed for me yonks ago with Allan VK6MST

2m and 70cm crossed yagi for satellite working - when I get around to finishing it, that is!

40, 20, 10 OCF dipole kindly given to me by Andrew VK6AS - taken down in prep for move to new QTH and previously has been in use for several field days including JMMFD with the WA VHF Group

80, 40, 20, 17, 10m a series of spiral wound vertical whips interchangeable on a spring base.   Originally designed for vehicle roo bar installation but modified for use with photographic light tripod as a base.   These have been in use with the FreeDV experiments despite non-optimal polarisation and shielding by buildings.

Magnetic loop (dual loops at 90 degrees) tunes well on 40m - constructed by Roger VK6FRAN   Needs a better capacitor and a means of remotely adjusting (geared motor, stepper, etc)

Mag loop from yellow gas tubing (metalised inner) - this is not yet functional, still considering the best way to implement a variable high voltage capacitor.

When I look back on the list it looks impressive but in fact only maybe 10% of the above are viable at present due to either not being finished or awaiting installation at new QTH.

Pipe-dream antennas - definitely a fan dipole a la VK3YSP and VK3FOWL (in AR magazine a few years ago they described it.)   More (and ever-better) mag loops.   I see these as the future for situations like mine where real estate is limited.   Microwave antennas and waveguides, etc as my interests expand into that area