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[TowerTalk] 80m Dipole ssb/cw switching

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Subject: [TowerTalk] 80m Dipole ssb/cw switching
From: K7GCO@aol.com (K7GCO@aol.com)
Date: Wed, 14 Nov 2001 05:34:26 EST
    Instead of external relays that short out linear loading for 80M 
suggested 
 below, why not have dipoles cut for SSB&CW at right angles to each other or 
 as close as 30 degrees and get an automatic and independant resonance on 
SSB&CW--as I suggested previously?  No Relays or trips outside in contests. 
See current CQ for another method.  

 A Bazooka will also assist in giving additonal bandwidth and balance 
 the coax. There are ABSOLUTELY NO RESISTIVE ELEMENTS IN A BAZOOKA OF ANY 
KIND EITHER. THERE ARE ONLY A FEW SPACERS SIMILAR TO OPEN WIRE LINE HOLDING 
THE BAZOOKA ELEMENTS 4-6" APART.  IT WILL TAKE AS MUCH POWER AS THE COAX 
ITSELF (THAT HAS BEEN FULLY TESTED EVEN WITH RG-58) WITH NO LOSS OR 
SATURATION OF CORES OF OTHER BALUNS--THERE ARE NO CORES IN A BAZOOKA EITHER.  
 
 There are circuits from the Stone Age of the Last Century that can still 
 improve your antennas performance--in this Century despite what the real 
 Stone Age RF Wizards claim.  A complete report and comparisons will be made 
 on the Bazooka and its affect on bandwidth and pattern in other mediums.  
 They actually pay for material that improves performance.  Unfortunately QST 
 still continues to show balanced feedpoints fed with unbalanced coax in 
2001. 
   K7GCO
 
 In a message dated 11/14/01 1:25:55 AM Pacific Standard Time, 
 Zoltan.Pitman@libertel.nl writes:<< 
  Rather than using banana plugs or alligator clips I suggest to cut the
  dipole to SSB and add a linear piece of linear loading at the feedpoint to
  both sides to retune the dipole to CW. If you want to operate on SSB you
  simply short the linear loading with a relay, which cancels the loading
  effect. I used this method on an Inv-Vee I still have. I needed 1.2m (4 ft)
  long loading element with 10+10cm (4") spacing (3530 for CW, and 3760 for
  SSB). The relays I used were common 400V/10A SPDT's fed via the coax, which
  would also suit you for 1500W.
  
  With this solution you get the luxury of not having to run out and climb
  towers in a multi-mode contests. :)
  Best regards,
  Zoli HA1AG
  
  > I just put up a 75m ssb antenna for ss this weekend.  I'm 
  > going to add 4 or 5 feet of wire at each end of the antenna by 
     attaching the wire to the current end insulator.
  > 
  > Whats the best way to provide a jumper so I can quickly drop 
  > the antenna attach the jumper so the antenna will reasonate on 80m cw?
  > 
  > I was thinking about heavy duty alligator clips or something, but what
  > about the tarnished copper, will the clip make a reliable connection?
  > Can it handle 1500 watts? You get the picture, any ideas? Thanks.
  > Richard Thorne - N5ZC
   

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