[600MRG] Off topic...sort of...

[Brian, WA1ZMS]

Ken-

Been thinking about for a while. An interesting problem.

The only solution that would really work would be a transformer where the feedline attaches to the V-beam.  That should keep the currents in the open wire equal.

I am thinking of a transformer like was often used in the link coupling output of 1930's transmitters.  You could make it a 1:1 xfmr and tune at the shack end of the line.  The tough part would be to wind big enough coils for your lowest band and still not make it so big that it can be put inside say a plastic soda bottle.  It would stay dry and still be light enough to be supported by tree ropes if you can RTV the wires, etc...

What you might try is to replicate the xfmr of an old Johnson Viking kW Matchbox. At least that's what I am thinking of.

-Brian, WA1ZMS
iPhone

> On May 6, 2018, at 3:06 PM, Kenneth G. Gordon <kgordon2006 at frontier.com> wrote:
> 
> OK, Gang, I finally managed to get my "new" HF antenna installed last week with the help of 
> two of the locals.
> 
> Here are some details: it is a Vee-Beam, with legs 120 feet long, but "swung" 90 degrees 
> with the end of one leg way up in our 110 foot tall pine tree in the back yard, and the end of 
> the other leg at ground level below the "upper" leg.
> 
> I am feeding it with 600 ohm open-wire-line, and, for obvious reasons, the current in the legs 
> is not balanced. I am getting a lot of radiation from the feed-line.
> 
> I am going to build Lloyd Butler VK5BR's Transmission Line Balance Test Meter to see just 
> how bad the imbalance is, and I hope I can correct this some way. Lloyd's meter is 
> essentially two RF ammeters in one box with a way to switch between the two legs.
> 
> Have I given you enough information for you to suggest some way to balance the feed?
> 
> I am "tuning" this with my Heathkit 2060A antenna coupler with integral balun, and am able 
> to achieve a 1:1 SWR on any frequency I care to tune it to, but I do have at least two true 
> balanced-couplers, one of which is a Johnson matchbox. From my previous experience with 
> my home-made balanced coupler, I think I can offset the connections to the coil so that I can 
> achieve true balance, but will value any suggestions you can make to help this situation.
> 
> Ken W7EKB
> 
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