It can be made to work (kinda) but not like shown in the figure. With a
130 ft dipole the two ladderline sections will have to be much longer,
about 60 to 70 ft long each, depending on how close you put it to the
top wire. You will find that the feedpoint impedance will be very low
and you will need a hairpin match at the feedpoint to match it to 50
ohms. You will also find that the bandwidth will be extremely narrow,
probably less than 10 KHz. It's also not very efficient.
For a commercial version of this idea check out the Cobra antenna. They
make no attempt to match it however, and just feed it with ladderline.
Jerry, K4SAV
Marc Tessier - VE3TES wrote:
>Just playing around with an antenna design , I found the plans for an 80M
>version of such antenna on the net recently, and was wondering if this one
>might work for 160M as well, link >>>
>http://home.cogeco.ca/~ve3tes/linear%20loaded%20160m%20dipole.JPG
>
>and would it be possible to make this into a twin band dipole by adding relays
>to short out the lengths of ladder line? as shown here as switches >>>
>http://home.cogeco.ca/~ve3tes/linear%20loaded%20160m%20dipole-80switch.JPG
>
>Just looking for some input, after running the CW test on the weekend from my
>80M dipole I figured this band could be some real fun, so time to start
>thinking of a more efficient antenna for 160...
>
>Regards,
>
>Marc Tessier - VE3TES
>
>ve3tes@cogeco.ca
>http://home.cogeco.ca/~ve3tes/
>http://www.eQSL.cc/Member.cfm?VE3TES
>http://www.qrz.com/ve3tes
>___
>
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