KL7UW
HF TOPICS 


  I operate the FT-847 on HF at 100 watts using either an 80-40m dipole or the TH3-mk4 
  Tri-band yagi (20-15-10m).  Since moving to the new QTH in August, 2006, I hope to 
  set up a 50-foot tower for mounting my Tri-band yagi and support the 80-40m inverted vee
  dipole and a 17m sloper diplole.

  I occasionally operate on 20m PSK-31 and check into the 14.345 MHz weekend EME Net at
  1700 utc.   On 80m I occasionally check into Nets on 3.933 MHz:
    

  • the Motley Group on week nights at 2100 local time.
    • 

  • the Swap-N-Shop Net on Saturday mornings at 1000 local time.


  I have a Swan Mk-III commercial linear that covers 2-16 MHz using a pair of 3-400z for
  1000w input on SSB.  The Swan HV power supply does double-duty providing power for
  my 144 MHz and 1296 MHz amplifiers.

  Examining the layout of towers at the new QTH, they are well situated to support a 
  130 foot horizontal wire at 40-50 feet above ground.  This provides the opportunity to
  put up an 80 meter Half-Square antenna beaming toward 145 degrees (West Coast USA) and
  325 degrees to Asia.

  The HF Tower can support the inverted vee at right angles to the Half-square, favoring 
  local Alaska coverage (55 degrees), and South Pacific (235 degrees).  More detail about 
  the HF Tower can be seen on the Six Meter Page.



  I am getting interested in the experimental activities of the 500-KHz (600m) Medium Wave
  Group (WD2XSH) and looking at low-noise receiving antennas to use with my SDR 
  to monitor the band.  A Beverage would be nearly 1000-foot long which would exceed my 
  property boundaries, whereas converting the half-square into a "EWE" antenna would be simpler.
  I am also considering a large square multi-turn loop.  I am not considering transmitting on 
  the 600m band but may on 160m.  

  This antenna may be modified into an EWE antenna for use on 160 meters and 600 meters by
  extending each vertical lead to ground by use of HV relays K2 and K3.  A 850-ohm load 
  added at the HF Tower vertical ground end, and fed thru a toroidal transformer at the
  EME Tower ground end provides a beam oriented on 60-degrees azimuth to Canada and the
  northern tier of US states.  The 80 meter feed would be shorted by K1.

  This could also be configured as a 160m inverted-L if only relay K3 is energized.  The 80m 
  feed presents an open circuit at 160m.

  Here is the NEC4win95 antenna analysis of the antenna:

  80 Meter Half Square:
  160 Meter Inverted-L:
  160 Meter EWE:
  600 Meter EWE:

  New J-Pole for 6m/10m Installed

  A combination J-Pole vertical antenna has been set up to permit working 6m FM stations and on 10m FM.
  Go to the J-Pole page
  


 
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