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[TowerTalk] (the) Actual Capacitor for Shunt-Fed Tower

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Subject: [TowerTalk] (the) Actual Capacitor for Shunt-Fed Tower
From: (Tom Rauch)
Date: Sat, 9 Feb 2002 05:48:25 -0500
> The center conductor of the coax 'capacitor' connected ONLY to the
> center conductor of the feedline, and the only the shield AT THE OTHER
> END of the 'capacitor' connected to the gamma rod.
> Surely this would be different than connecting the coax 'across' the
> feedline-gamma connection???

Good point! While that is a bit better for voltage, there is a much 
better way still.

Connect the shield of the "capacitor" to itself at both ends, and the 
center conductor to itself at both ends. Now the reactance is closer 
to the capacitance-per-foot value, peak voltage is reduced and 
appears midway down the cable, and loss resistance is reduced to 
1/4 the original value. Q is almost four times higher, and bandwidth 
is wider.

Good point Don, changing the connections makes a "free" 
improvement. You've now found a free lunch.

Notice how that makes the coax "capacitor" look more like a 
conventional capacitor?
73, Tom W8JI 

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