Dear fellow Top-Banders,
testing my new antenna - an 83ft elevated vertical with folded
elevated radials - I got a problem which I couldn't solve sofar.
The vertical is driven via a current type balun - 100 no.73 ferrite beds
slipped over a piece of teflon coax. The antenna itself is not
connected to ground, instead the shield of the coax cable is
grounded directly before going into the current balun.
If I penetrate the antenna with 500W for about 1 minute the balun
becomes very hot (you can't touch it anymore) and the SWR is increasing.
Now my question - what can be done to reduce the power, the balun has to
absorbe? Would it be helpful, to install a voltage type balun
(e.g. W6TC design) instead or a combination of both?
Any suggestion is welcome.
Please respond direct to dl8wpx@indo.net.id.
BTW - heard Mike, VK6HD working West Coast yesterday and
was at least able to copy some pieces of Tree's, N6TR signal.
It hopefully won't take long anymore that the paths running
further north will be open again ....
Best 73,
de Joerg, YB1AQS
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