Hi Steve -
You 've made a good point , however:
an 80m dipole at 30 feet isn't going to be 1:1 on 50 ohm line and,
how does it look off resonance out towards the band edges ?
Gene / W2LU
----- Original Message -----
From: "Steve Hunt" <steve@karinya.net>
Cc: "Towertalk" <towertalk@contesting.com>
Sent: Tuesday, January 17, 2012 12:25 PM
Subject: Re: [TowerTalk] Dipole fed with balanced line?
> Here are some "complete system" numbers drawn from EZNEC, VK1OD's line
> loss calculator, and W9CF's tuner simulator:
>
> Half-wave 80m dipole at 30ft made from #14 wire:
> Antenna copper losses: 0.19dB
> 100ft RG213 losses (matched): 0.35dB
> Tuner losses: zero - no tuner needed
> Total loss: 0.54dB
>
> 100ft dipole at 30ft made from #14 wire:
> Antenna copper losses: 0.24dB [radiation resistance is lower, so more
> current for same power; but compensated by antenna being shorter and
> therefore total RF resistance less]
> 100ft Wireman554 ladderline losses (24-j490 load): 1.75dB
> Tuner losses (1139+j3215 load): 0.2dB
> Total loss: 2.19dB
>
> Difference: 1.65dB !!!
>
> 73,
> Steve G3TXQ
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|